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