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Understanding Medical Terms

At first glance, medical terminology can seem like a foreign language. But often the key to understanding medical terms is focusing on their components (prefixes, roots, and suffixes). For example, spondylolysis is a combination of "spondylo, " which means vertebra, and "lysis," which means dissolve, and so means dissolution of a vertebra.

The same components are used in many medical terms. "Spondylo" plus "itis, " which means inflammation, forms spondylitis, an inflammation of the vertebrae. The same prefix plus "malacia, " which means soft, forms spondylomalacia, a softening of the vertebrae.

Knowing the meaning of a small number of components can help with interpretation of a large number of medical terms. The following list defines many commonly used medical prefixes, roots, and suffixes.

a(n)

absence of

acou, acu

hear

aden(o)

gland

aer(o)

air

alg

pain

andr(o)

man

angi(o)

vessel

ankyl(o)

crooked, curved

ante

before

anter(i)

front, forward

anti

against

arteri(o)

artery

arthr(o)

joint

articul

joint

ather(o)

fatty

audi(o)

hearing

aur(i)

ear

aut(o)

self

bi, bis

double, twice, two

brachy

short

brady

slow

bucc(o)

cheek

carcin(o)

cancer

cardi(o)

heart

cephal(o)

head

cerebr(o)

brain

cervic

neck

chol(e)

bile, or referring to gall-bladder

chondr(o)

cartilage

circum

around, about

contra

against, counter

corpor

body

cost(o)

rib

crani(o)

skull

cry(o)

cold

cut

skin

cyan(o)

blue

cyst(o)

bladder

cyt(o)

cell

dactyl(o)

finger or toe

dent

tooth

derm(ato)

skin

dipl(o)

double

dors

back

dys

bad, faulty, abnormal

ectomy

excision (removal by cutting)

emia

blood

encephal(o)

brain

end(o)

inside

enter(o)

intestine

epi

outer, superficial, upon

erythr(o)

red

eu

normal

extra

outside

gastr(o)

stomach

gen

become, originate

gloss(o)

tongue

glyc(o)

sweet, or referring to glucose

gram, graph

write, record

gyn

woman

hem(ato)

blood

hemi

half

hepat(o)

liver

hist(o)

tissue

hydr(o)

water

hyper

excessive, high

hypo

deficient, low

hyster(o)

uterus

iatr(o)

doctor

infra

beneath

inter

among, between

intra

inside

itis

inflammation

lact(o)

milk

lapar(o)

flank, abdomen

latero

side

leuk(o)

white

lingu(o)

tongue

lip(o)

fat

lys(is)

dissolve

mal

bad, abnormal

malac

soft

mamm(o)

breast

mast(o)

breast

megal(o)

large

melan(o)

black

mening(o)

membranes

my(o)

muscle

myc(o)

fungus

myel(o)

marrow

nas(o)

nose

necr(o)

death

nephr(o)

kidney

neur(o)

nerve

nutri

nourish

ocul(o)

eye

odyn(o)

pain

oma

tumor

onc(o)

tumor

oophor(o)

ovaries

ophthalm(o)

eye

opia

vision

opsy

examination

orchi(o)

testes

osis

condition

osse(o)

bone

oste(o)

bone

ot(o)

ear

path(o)

disease

ped(o)

child

penia

deficient, deficiency

peps, pept

digest

peri

around

phag(o)

eat, destroy

pharmaco

drug

pharyng(o)

throat

phleb(o)

vein

phob(ia)

fear

plasty

repair

pleg(ia)

paralysis

pnea

breathing

pneum(ato)

breath, air

pneumon(o)

lung

pod(o)

foot

poie

make, produce

poly

much, many

post

after

poster(i)

back, behind

presby

elder

proct(o)

anus

pseud(o)

false

psych(o)

mind

pulmon(o)

lung

pyel(o)

pelvis of kidney

pyr(o)

fever, fire

rachi(o)

spine

ren(o)

kidneys

rhag

break, burst

rhe

flow

rhin(o)

nose

scler(o)

hard

scope

instrument

scopy

examination

somat(o)

body

spondyl(o)

vertebra

steat(o)

fat

sten(o)

narrow, compressed

steth(o)

chest

stom

mouth, opening

supra

above

tachy

fast, quick

therap

treatment

therm(o)

heat

thorac(o)

chest

thromb(o)

clot, lump

tomy

incision (operation by cutting)

tox(i)

poison

uria

urine

vas(o)

vessel

ven(o)

vein

vesic(o)

bladder

xer(o)

dry