Medical Root Words and Combining Forms

Medical root words are used in the formation of medical terminology. Most of the root forms are taken from Greek and Latin words. The prefixes and suffixes that are taken from these former words have a droppable 'o'. The 'o' acts as a joint stem to connect two consonant roots eg. amni + o + cele = amniocele. Generally 'o' is dropped when connecting to a vowel stem, eg. bronch + itis = bronchitis. There are good number of medical words that exist today and many more are developing with the advancement of medical science. Medical root words helps in identifying and understanding a medical term easily and clearly. Here is a list of medical root words and combining forms.

Root Word/            Definition                          Medical Word

Combining Form

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abdomin/o-             abdomen                               abdominal

acanth/o-                thorn, spine                           acanthoma, acanthaceous,  acanthocyte

acetabul-                hip socket                              acetabulum

acous/io-                hearing                                 acoustic, acoumeter, acoustician

acr/o-                     extremities, topmost               acromion, acral, acromegaly

actin-                     ray, radius                              actinic

aden/o-                   relating to gland                      adenocarcinoma,  adenology, adenotome

adenoid/o-               adenoids                                adenoiditis

adip/o-                    relating to fat                         adipose tissue, adipocyte

adren/o-                  relating to adrenal gland          adrenal artery

aer/o-                     air, gas                                  anaerobic, aerate

albumin-                 albumin                                 albuminuria
alge/si-                   pain                                       analgesic

algi/o-                     pain                                      myalgia

algesi/o-                  pain                                      analgesia

alveoli/o-                 alveolus                                alveolitis

ambly/o-                 dull, dim                               amblyopia

amni/o-                   amnion                                 amniocele

amnion/o-               amnion                                 amnionic

amyl/o-                   starch                                  amylose

an/o-                      anus                                     anus

andr/o-                   male                                     androgen, andrology

angi/o-                    blood vessel                          angina, angiogram

anis/o-                    unequal, dissimilar                 anisothenic, anisocytosis, anisotropic

ankyl/o-                  crooked, bent, fused              ankylosis

antr/o-                    cavity, chamber                     antrum

anter/o-                  front                                     anterior

aort/o-                    aorta                                    aortic

aponeur/o-              aponeurosis                           aponeurotic

append/o-               appendix                               appendicitis

arche/o                  first, beginning                       archecentric, archinephron

arteri/o                  pertaining to an artery             arteriography,

arteri/o                  arteriole, small artery               arteriolosclerosis, arterial

arthr/o                  pertaining to joints, limbs          arthritis

articul/o                joint                                       articulation

atel/o                    incomplete, imperfect              atelectasis, atelocardia

ather/o                  yellowish, fatty plaque             atherosclerosis

atri/o                    atrium, chamber                      atrioventricular

aur/o                    pertaining to ear                       aural, auricle

aut/o                    self                                         autoantibody, autoimmune
aux/o-                   increase, growth                     auxocardia

axill/o-                   pertaining to armpit                 axilla

azot-                     nitrogen compound                  azotemia, azothermia

bacteri/o-               bacteria                                  bacterial, bacteriophage

balan/o-                 glans penis, or glans clitoridis   balanitis

bio-                      life                                         biology

bil-                       bile                                         biliary

blast/o-                  germ, developing cell               blastoctye, blastomere

blephar/o-              pertaining to eyelid                   blepharoplast

brachi/o-               arm                                        brachial artery

bronch/i-              bronchus                                 bronchitis

bronchiol-              bronchiole                              bronchiole, bronchiolitis obliterans

bucc/o-                 pertaining to cheek                   buccal, buccolabial

burs/o-                  bursa, cavity                           bursitis

calc-                     calcium                                  calcium

calcane/o-              heel bone                                calcaneus

carcin/o-                cancer                                   carcinoma, carcinogenic

cardi/o-                  pertaining to heart                   cardiac, cardiology

carp/o-                   pertaining to wrist bone           carpal tunnel, carpopedal

caud-                     tail, lower part                        caudal

cec-                       cecum                                   cecal

celi-                       abdominal cavity                     celioenterotomy

cephal/o-                pertaining to head                    cephalad, cephalic
cerat/o-                  pertaining to cornu, a horn       ceratoid

cerebell/o-              pertaining to cerebellum            cerebellar

cerebr/o-                pertaining to brain                   cerebromedullary, cerebroside

cerumin-                cerumen, earwax                    ceruminal

cervic/o-                neck                                      cervical

chem/o-                 chemistry, drug                      chemotherapy

cheil-                     lip                                         cheilitis

chir/o-                   pertaining to hand                    chirality, chiropractor

chlor/o-                 green color                             chlorophyll

chol/e/o-                 pertaining to bile, gall              cholaemia
cholecyst/o-           pertaining to gallbladder           cholecystectomy

chondr/i/o-            cartilage, granule, granular       chondral, chondrocalcinosis

chori-                    chorion                                  chorioretinal

chromat/o-             color                                     chromatogenous, hemochromatosis

claviculo-               collar bone, clavicle                clavicular

coccygo-               tail bone                                 coccygeal

colo-                     colon                                     colonitis

colp/o-                  pertaining to vagina                  colposcopy

coron/o-                crown                                    coronitis

coni-                     dust                                       coniosis

conjunctiv-            conjunctiva                             conjunctivitis

cor-                       pupil                                      corectasis

corne-                   cornea                                    corneal

cortic-                   outer layer                              cortical

cost/o-                   pertaining to ribs                    costicervical

crani/o-                  relating to skull                       cranial

crin/o-                   secretion                                endocrine

cry/o-                    cold                                      cryotherapy, cryoablation

crypt-                    hidden                                   cryptic

cutane/o-               skin                                       subcutaneous

cyan/o-                  blue color                              cyanotic, cyanopsia

cyes-                     pregnancy                              cyesis
cyph/o-                  bent                                      cyphosis                      

cyst/o-                   bladder, sac                            cystic, cystotomy

cyt/o-                    cell                                        cytology, cytokine

dacry/o-                 tears, tear duct                       dacryoadenitis

dactyl/o-                pertaining to finger, toe            dactylolysis

dent/o-                   tooth                                     dentition

derm/o-                  pertaining to skin                    dermis

dermat/o-               pertaining to skin                    dermatology

dextr/o-                  right side                               ambidextrous, dextrocardia

diaphor-                 sweat                                    diaphoresis

diaphragmat-          diaphragm                              diaphragmatitis

dipl/o-                    two, double                            diplopia

dips/o-                   thirst                                      dipsosis, polydipsia

disk-                      intervertebral disk                    diskectomy

diverticul-              diverticulum                            diverticulitis

dors/o-                  pertaining to back                   dorsal

duoden/o-              duodenum                              duodenal

dur/o-                   dura mater                              dural

dynam/o-              power, energy, force                dynamogenic

ech/o-                  sound                                     echocardiogram
ect/o-                    outer, outside                         ectoblast, ectoderm

ectop-                    located away                          ectopic pregnancy

electr/o-                 electricity                               electrocardiogram

embry-                  embryo, to be full                    embryonic

emmetr-                normal measures                      emmetropia

encephal/o-            pertaining to brain                    encephalitis, encephalogram

endocrin-               endocrin                                 eendocrinosis
eosin/o-                red                                         eosinophil granulocyte

enter/o-                  pertaining to intestine               enteritis, gastroenterology

epididym-               epididymis                              epididymal

epiglott-                 epiglottis                                 epiglottiditis

episi/o-                   pubic region, loins                   episiotomy

epitheli/o-               epithelium                               epithelial

erythr/o-                 red                                        erythematous, erythrocyte

esophag/o-              esophagus                              esophagocele

esthesi/o-               sensation, sensitivity                  anesthesia

eti/o-                      cause                                      etiology

faci/o-                    pertaining to face                      facioplasty, facioplegic

femur/o-                 femur, thigh bone                      femoral

fet-                        fetus, unborn child                    fetal

ferro/o-                  iron                                         ferritin

fibr/o-                    fiber, fibrous tissue                    fibroma, fibroblast

fibul/o-                   fibula, lower leg bone                fibular

gangli-                    ganglion                                   ganglia

galact/o-                 milk                                         galacturia, galactorrhea

gastr/o-                  pertaining to stomach                gastritis

ger/o-                     old age                                    geriatric

geront/o-                 old age                                   gerontology

gingiv/o-                 gum                                       gingivitis
glauc/o-                 grey or bluish-grey colour        glaucoma

glomerul/o-             glomerulus                              glomerulonephritis

gloss/o-                  pertaining to tongue                  glossopharyngeal, glossology
glott/o-                  pertaining to tongue                  epiglottis  

gluc/o-                   glucose                                   glucose

glyc/o-                   sugar                                      glycerin

glycos/o-                sugar                                     glycosamine

gnath/o-                  pertaining to jaw                     orthognathia, gnathodynamometer

gnos/o-                   knowledge                             gnosis

gon/o-                    seed, semen                           gonad, gonorrhea

gravid/o-                 pregnancy                             gravida

gyn/o-                    female                                   gynopathic

gynec/o-                 female                                   gynecology, gynecomastia

hem/o/a-                 blood                                     hemoglobin

hemat/o-                 blood                                     hematocrit

hepat/o-                  liver                                       hepatitis

herni/o-                   hernia                                     herniated

heter-                     other                                       heterosexual

hidr/o-                    sweat                                     hidradenoid

hist/o- or histi/o-     tissue                                     histology

hom/o-                   same                                     homogeneous

humer-                   humerus, upper arm bone         humerus

hydr/o-                   water                                     hydrate

hymen-                   hymen                                    hymen

hypn/o-                  sleep                                       hypnogenic

hume/o-                  humerus                                 humeral

hydr/o-                   water                                     hydrate, dehydrate

hymen-                   hymen                                   hymen

hypophys/o-            pituitary gland                         hypophyseal

hyster/o-                 uterus                                    hysterectomy

iatr/o-                     treatment, medicine                  iatrogenic

ichthy/o-                 fish                                         ichthyoid

ile/o-                      ileum                                      ileotomy

ili/o-                       ilium                                       iliosacral

immune-                immune                                  immunodeficiency

Iri/o-                      iris                                         iritoectomy

Irid/o-                    iris                                         iritis

Is/o-                      equal, same                              isocellular

Isch-                     deficiency; blockage                 ischemia

Ischi-                     ischium                                  ischiorectal

inguin/o-                groin                                     inguinal

jejun/o-                  jejunum                                  jejunotomy

kal/o-                    potassium                              hypokalemia

kary-                     nucleus                                  karyon

kerat/o-                 cornea                                   keratotomy

kerat-                    horny tissue; hard                    keratosis

kin/o-                    move, movement                      kinesis

kinesi/o-                motion, movement                   kinesiology

kyph-                    hump                                     kyphosis

labi-                      lips                                        labium

labyrinth-               labyrinth                                 labyrinthitis

lacrim/o-                tears, tear duct                        lacrimal

lact/i/o-                  milk                                       lactation

lamin-                    lamina, thin, flat plate               laminar

lapar/o-                  abdomen                                 laparoscopy

laryng/o-                larynx                                    laryngitis

later/o-                   lateral, side                              lateral

lei/o-                      smooth                                     leiomyoma

leuk/o-                   white                                       leukemia

lingu/o-                  tongue                                      lingual

lip/o-                     fat                                            lipid

lith/o-                    stone, calculus                          lithotripsy

lob-                       lobe                                        lobular

lord-                      bent forward                           lordosis

lymph/o-                lymph                                     lymphoma

lys/o-                     dissolution                               lysis

macr/o-                  large                                       macrocyte

mamm/o-               breast                                      mammary

mast/o-                  breast                                      mammary

mandibul-               mandible, lower jaw                 mandibular

mastoid-                 mastoid                                   mastoidotomy

maxxill/o-               jaw, upper jaw                         maxillary

meat/o-                   meatus                                    meatus

megal/o-                 large                                      megaloblasts

melan/o-                 black                                     melanoma

men/o-                   menses                                   menstrual, menstruation

mening/o-               meninges                                meningitis

meninge/o-             meninges                                meningitis

menisci-                 meniscus                                meniscus

ment/o-                  mind                                      mental

ment/o                  hyoid bone                             submental

metr/o-                   uterus                                    metroptosis

metacarp/o-            wrist bone                              metacarpals

metatars/o-             foot bone                                 metatarsals

mon/o-                   one                                        monoparesis

morph/o-                form, shape                            morphology

mucu/o-                 mucus                                    mucosal

muscul/o-               muscles                                  myasthenia

my/o-                     muscle                                   myofibrils

myc/o-                   fungus                                    mycete

myel/o-                   bone marrow                          myeloma, myelonic

myring/o-               ear drum                                myringoplasty

narc/o-                   stupor                                    narcotic

nas/o-                     nose                                      nasal bone

nat/o-                      birth                                      prenatal

necr/o-                   death, dead cells                     necrosis

nephr/o-                  kidney                                   nephritis

neur/i/o-                  nerve                                     neuropathy

noct/o-                   night                                      nocturnal

nyct-                      night                                      nycterine

norm/o-                  normal                                    normotensive

nos/o-                    disease                                    nosocomial

obstetr/o-               pregnancy                               obstetrics

ocul/o-                   eye                                          ocular

odont/o-                 teeth                                        odontogenic

odyn/o-                  pain                                         odynophagia

olig/o-                    scanty, few, little                       oliguria

omphal-                  umbilicus, navel                         omphaloma

onc/o-                    tumor                                      oncology

onych/o-                 nail                                         onychogenic

o/o-                        egg, ovum                                oocyte

oophor/o-                ovary                                        oophorectomy

ophthalm/o-             eye                                           ophthalmology

opt/o-                     vision, eye                                optical

or/o-                      mouth                                       oral

orch/i/o-                 testis, testicle                            orchilytic, orchiectomy

orth/o-                   correct                                    orthopnea

organ/o-                 organ                                        organic

osm/o-                   osmosis                                    osmotic pressure

osse/o-                   bone                                         osseointegration

oste/o-                    bone                                         osteoporosis

ot/o-                       ear                                            otitis

ov-                         egg                                            ovum

ovari/o, ovi/o-          ovary                                         ovarian cyst

ox/o-                      oxygen                                      oxidation

pachy/o-                 thick                                          pachycephalic

palat/o-                   palate                                         palatoplegia

pancreat/o-             pancreas                                     pancreatic

path/o-                   disease                                       pathology

papill/o-                  nipple                                         papillary

par/o-                    bear, give birth                            para

parathyroid-            parathyroid gland                       parathyroidoma

part-                      bear, labor                                  postpartum

patell/o-                 patella, knee-cap                         patellar reflex

pector/o-               chest                                         pectoral girdle

ped/o-                   child                                          pediatrics

ped/o-                   foot                                           pedal

pelv/i/o-                 hip bone, pelvis                          pelvic bone

perine-                   perineum                                    perineum

peritone-                peritoneum                                 peritoneal

petr-                      stony, hard                                 petrous part

phac/o-                  lens of the eye                            phacolysis

phag/o-                  eat, swallow                                phagocytosis, dysphagia

phak/o-                  lens of the eye                            phakomatosis

phalang/o-              pharynx                                      phalangeal

phas-                     speech                                       aphasia

pharmac/o-            drug                                          pharmacology

pharyng/o-             pharynx                                     pharyngitis

phleb/o-                 vein                                           phlebitis

phob/o-                 fear                                           agoraphobia

phon/o-                 sound                                        phonology

phot/o-                  light                                          photokinetic

phren/i/o-              diaphragm                                 diaphragmatic breathing

phren/o-                mind                                         phrenology

physi-                   nature                                        physiology
plasm-                   plasma                                       plasmacyte

plasi/o-                  formation, growth                       achondroplasia

plesi/o-                  near, close                                  plesiomorphic

pleur/o-                 pleura                                        pleuracentesis

pneum/o-               air, lung                                     pneumogastric, pneumonia

pneumat/o-             air, lung                                   pneumathemia

pod/o-                    foot                                        podiatry

poikil/o-                  varied, irregular                       poikiloblast

poli/o-                    gray matter                              poliodystrophia

polyp/o-                 small growth                            polypoid

poster/o-                behind, back                            posterior

prim/o-                  first                                        primary

presby/o-               old, old age                              presbyacusis

proct/o-                 rectum                                    proctology

prostate/o-             prostate gland                          prostatitis

pseud/o-                fake, false                               pseudopolyp

psych/o                mind                                      psychiatry

pub/o-                    pubis                                      pubic

puerper-                 childbirth                                 puerperal

pulmon/o-               lung                                         pulmonary

pupil-                     pupil                                        pupillary reflex

py/o-                     pus                                         empyema

pyel/o-                   pelvis                                       pyelogram

pylor-                    pyloric sphincter                       pylorostomy

pyr/o-                   fever, heat                                pyrogenic

quadr-                   four                                        quadruplets

rachi/o-                 spine, vertebra                          rachiocentesis

radi/o-                   lower arm bone                        radius

radi/o-                   x-ray                                       radiography
radic-                    nerve root                                radiculopathy

rect/o-                  rectum                                     rectocele

ren/o-                   kidney                                      renal

reticul/o-                net                                          reticulum

retin/o-                  retina                                       retinosis

rhabd/o-                rod shaped, striated                   rhabditis

rhin/o-                   nose                                        rhinitis

rhiz/o-                   nerve root                                rhizoneure

rheumat/o-            flux that flows, a stream            rheumatism

rhytid-                    wrinkles                                   rhytidoplasty

sacr/o-                   sacrum                                    sacroiliac

salping/o-               fallopian tube                            salpingitis

sarc/o-                   flesh, connective tissue             sarcocele

scapul/o-                scapula, shoulder bone              scapular

schist/o-                 split, cleft                                schisophrenic
schiz/o-                  division, split                            schizencephaly

scler/o-                  sclera                                      sclerectomy

scoli/o-                  curvature, twisted                     scoliokyphosis

seb-                       sebum, oil                                sebaceous

sept/o-                   septum, partition                      septum

septic/o-                decay, rot                                 antiseptic

sial/o-                    saliva                                      salivary

sigmoid-                sigmoid                                   sigmoidoscopy

sinus-                    sinus                                       aerosinusitis

sit/o-                     food, eating                              antiparasitic

somat/o-                body                                       somatometry

somn-                    sleep                                      insomnia

son-                       sound                                    sonogram

sperm/o-                semen, sperm                         spermiduct

spermat/o-             spermatozoan, sperm               spermatorrhea

sphygm-                pulse                                      sphygmomenometer

spir-                      breathe, breathing                    transpiration

splanchn/o-            viscera, intestines                    splanchnic

spleen-                   spleen                                    spleen

spin/o-                   spine, thorn, prickle, brain        cerebrospinal
spondyl/o-         vertebra, spinal, vertebral column   spondylosis

splen/o-                 spleen                                      spleen

spondyl/o-             vertebra                                   perispondylitis

staped-                   stapes, middle ear bone              stapedial
staphyl/o-               clusters, grapelike clusters          staphylococcus

stern/o-                  sternum, breast bone                  sternal

steth-                     chest                                        stethoscope

stom/o-                  mouth                                      stomatitis

stomat/o-                mouth                                      stomatoplasty

strept/o-                 twisted chains                           streptococcus

tars-                       tarsals, ankle bones                     metatarsal

tars/o-                    edge of eyelid, tarsal                   tarsitis

ten-                        tendon                                      tendon

tend/o-                   tendon                                      tendotomy

tendin/o-                 tendon                                      tendinitis

test-                       testis, testicle                             testicular

therm/o-                 heat                                          thermal

thorac-                   thorax, chest                             thoracic

thel/o-                     nipples                                     thelarche

therm/o-                  heat                                         thermometer

thorac/o-                chest, thorax                            pneumothorax

thromb/o-               clot, lump                                thrombus, thrombectomy

thym/o-                   thymus gland                            thymolysis

thyr/o-                    thyroid gland                             thyroid

tibi/o-                     tibia, lower leg bone                  tibial

tom/o-                    cut, section                              tomography

toc/o-                     child                                        atocia

ton/o-                     tension, pressure                      tonicity

tonsil/o-                  tonsils                                     tonsillitis

top/o-                     place                                       topographic

tox/i/o-                   poison                                     toxin

trache/o-                 trachea                                    tracheobronchial

trachel/o-                neck, neck like                         trachelitis

trich/i/o-                 hair                                          trichoid

troph/o-                  food, nutrition                           abiotrophic

tympan/o-               eardrum, middle ear                 tympanic membrane

uln/o-                     ulna, lower arm bone                ulnar

ungu/o-                  nail                                          ungual

ur/o-                      urine, urinary tract                     urinary

ureter/o-                 ureter                                       ureteroplasy

urethr/o-                 urethra                                    urethrectomy

uter/o-                    uterus                                       intrauterine

urin/o-                    urine, urinary tract                     urinalysis

uvul-                      uvula                                        uvuloptosis

vagin/o-                  vagina                                     vaginal

valv/o-                    valve                                         valvula

valvul-                    valve                                          valvuloplasty

vas/o-                     vessel, duct                                vasectomy

vascul/o-                 vessel, tubes, ducts                      avascular

ven/o-                     vein                                           venous

ventricul/o-              ventricle                                    ventricular

venul/o-                   venules, small veins                     venular

vertebr/o-                vertebra, spinal column               costovertebral

vesic/o-                   bladder, sac                               vesical

vesicul/o-                seminal vesicles                          vesiculation

viscer/o-                 internal organs                            viscera

vulv/o-                    vulva                                         vulvitis

xanth/o-                  yellow                                       xanthoma

xer/o-                     dry                                             xerosis, xerophthalmia

zo/o-                      animal, living beings                      azoospermia

zym/o-                   enzyme, ferment                           enzymatic, lysozyme