Decoding Medical Terminology:
Definitions of Commonly Used Greek & Latin Roots and Affixes
Prepared by Dr. Sandy Dolan, Office of Medical Education

a-	without, not or lack of		macro-	big
ab-	from, away from		mal-	ill, bad, poor
abrad/o, abras/o	rub or scrape off		malacia	softening
acr/o	extremity, height		mamm/o	breast
ad-	to, toward, near		mandibul/o	mandible
aden-	gland		mast/o	breast
adren/o	gland		med/i	middle
adenoid/o	adenoid		megaly	enlargement
adip/o	fat		melan/o	black
adren/o	adrenal		mes/o	middle
adrenal/o	adrenal gland		meta	beyond, change
agglutin/o	clumping, sticking together		metr/o	uterus, womb
agra-	seizure of pain		micro-	little
aise-	comfort, ease		mono-	one
alb-	white		morph-	form, shape
algesia	pain		muc/o	mucous mucus
algia	pain		multi-	many
aliment/o	nourish		mycosis	fungal infection
alveol/o	alveolus, air sac		myel/o	spinal cord, bone marrow
ambly/o	dull, dim		my/o	muscle
amph/i	doubly, both		myc/o	fungus
angio	vessel		myring/o	tympanic membrane, eardrum
an-	without, not, or lack of
an/o	anus		nas/o	nose
andr/o	male		nat/o	birth
ankyl/o	stiff joint, fusion		ne/o	new
anomal/o	irregularity		necr/o	death
ante-	before/in front of		nephr/o	kidney
anter/o	before, in front of		neur/o	nerve, neuron
anthrac/o	coal dust		noct/o	night
anti-	against		nucle/o	nucleus
aort/o	aorta
aque/o	water		ocul/o	eye
arche	beginning		odont/o	teeth
are/o	a little open space		-oid	resemble
arteriol/o	little artery, arteriole		olig/o	scanty
arthr/o, articul/o	joint		-ology	study of
asthenia	without strength		oma, onc/o	tumor
atel/o	incomplete, imperfect		omphal/o	navel
ather/o	fatty deposit, fatty degeneration		onchy/o	nail
atri/o	atrium		oo-	egg
audio	hearing		oophor/o	ovary
azot/o	urea, nitrogen		opia, opsia, opt/o	vision
			or/o	mouth
balan/o	glans penis		orch/o, orchid/o	testes
bi-	two		-orrhaphy	suture
bili/o	bile		-orrhea	flow, discharge
bio-	life		orth/o	straight
blast	primitive cell, embryonic		-osmia	smell
blephar/o	eyelid		ose/o, osseo	bone
branchi/o	arm		ot/o	ear
brady-	slow
bronch/o	bronchus, bronchi		pachy/o	heavy, thick
bucc/o	cheek		pan-	all
burs/o	sac or cavity		papul/o	papule, pimple
			para-	beside, beyond, abnormal
calc/i	calcium		paresis	partial or incomplete paralysis
calcane/o	calcaneous		path/o, pathy	disease
cali/o	calyx, calyces		penia	decrease
capnia	carbon dioxide		peps/i, pept/o	digestion
carcin/o	cancer		peri-	around
cardi/o	heart		petechi/o	skin spot
carp/o	carpal		pexy	fixation, suspension
cartilag/o	cartilage		phac/o	lens
caud/o	tail		phagio-	swallowing
cec/o	cecum		phall/o	penis
cele-	hernia swelling		-phasia	speech
cellul/o	cell		-philia	attraction to
centasis	surgical puncture		phleb/o	vein
cephal/o	head		-phobia	fear (of)
cerebell/o	cerebellum		phonia	voice, sound
cerebr/o	cerebrum		phren/o	diaphragm, mind
cerumin/o	ear wax		phylactic, phylaxis	protective, preventative, protection
cervico	cervical bone, cervix, neck		physis	grow, growing
cheil/o	lip		pil/o	hair
chlor/o	green		pineal/o	pineal gland
chol/o	bile, gall		phag-	eat
cholecyst/o	gallbladder		plakia	plate
choledoch/o	common bile duct		plasia, plasm	formation, growth, development
chole/o	bile/gall		plasty	formation, surgical repair, plastic repair
chondr/o	cartilage		plegia	paralysis (total)
choroid/o	bloody cord, choroid		plex	network, especially of nerves
chrom/o	color		pnea	breathing
chromat/o	color		pneumat/o	air, breath
cil/o	microscopic projections		pneumon/o	lung, air
circum	around		pod	foot
cirrh/o	yellow		-poiesis	formation, attraction
-clast	that which breaks or destroys		poli/o	grey
clavic/o	clavicle		poly-	many
colp/o	vagina		-porosis	pores or cavities
col/o	colon		presby/o	old age, elderly
coni/o	dust		primi	one
contra	against		proct/o	rectum and anus
contus/o	bruise		prot/o	first
cor/o	pupil		proxim/o	near
core/o	pupil		prurit/o	itch
coron/o	heart		pseudo-	false
cortic/o	cortex, outer surface of a structure		psych	soul, mind
cost/o	ribs		-ptosis	prolapse, falling, drooping
crani/o	skull		-ptysis	spitting
-crine	to secrete		pulmon/o	lung
cry/o	cold		purpur/o	purple
crypt/o	hidden sac or cavity		py/o	pus
-cusis	hearing		pyel/o	trough, basin, pelvis
cutane, cutis	skin		pylor/o	opening between stomach and duodenum
cyan/o	blue		pyorrhea	discharge of pus, purulent discharge
cycl/o	ciliary body		pyr/o	fever
cyesis	pregnancy
cyst/o	bladder		quad, quadr	four
cyt/o, cyte	cell
			rach/o, rachi/o	vertebrae
dacryl/o	tear		radicul/o	nerve root (of spinal nerves)
dactyl/o	digits		re-	back
de-	down, lack of		rect/o	rectum
dendr-	tree		ren/o	kidnery
derm/o, dermat/o	skin		retin/o	retina
desis-	binding, stabilization function		retro-	after, behind, backward
dextr/o	right		rhabd/o	rod-shaped, striated
di-	two		rhin/o	nose
dia-	across, through		rhytid/o	wrinkles
diaphor/o	profuse sweating		-rrhage	bursting forth (of)
diplo-	two		-rrheo	flow or discharge
dipsia	thirst		-rrhexis	rupture
dist/o	distant		rube/o	red
dors, dors/i, dors/o	back
dur/o	hard		sacr/o	sacrum
dynia-	pain		salping/o	fallopian, oviduct, uterine, eustachian tube
dys-	bad, painful, difficult		salpinx	trumpet shaped tube
			sarc/o	flesh
ec-	out, out from		schirrh/o	hard
ecto-	outside		scler/o	hard
ectomy	excision, removal		sclerosis	abnormal condition of hardening
embol/o	embolus, plug		scoli/o	crooked, curved
-emia	blood condition		scopy	visual examination
-emesis	vomit		seb/o	sebum
encephal/o	brain		semi-	half, partial
endo-	within		sepsis, sept/o	infection
enter/o	intestines		sept-	fence, wall
epi-	over		sect-	cut
episi/o	vulva		ser/o	serum, watery substance
erythr/o	red		seros/o	serous
erythem/o	redness		sin/o, sin/u	a hollow
erthyi/o	redness		sinistr/o	left
esthesia	feeling, sensation		sis (asis, esis, iasis, osis)	condition or state
eti/o	cause		som/o, somat/o	body
eu-	good		spas	draw, pull
ex-	out, out from		sphincter	valvelike muscle ring
exacerbat/o	irritate, aggravate		sphygm/o	pulse
exo-	outside		spir/o	breathe
extra-	outside, in addition to		splen/o	spleen
exud/o, exudat/o	to sweat out		spondyl/o	vertebrae (condition of the structure)
			squam/o	scale
fasci/o	fibrous membrane, a thin skin or film		stasis	control, stop, standing
febr/o	fever		steat/o	fat, sebum
flex	bend		stenosis	narrowing
flux, flu	flow		stern/o	sternum
front/o	frontal		steth/o	chest
			strepto	twisted chains
galact/o	milk		stixis	surgical puncture
gangli/on	knot		stoma, stomat/o	mouth
gastr/o	stomach		sub-	under, below
gen-	to produce		super, supra	above (position or amount)
gest-	bear, carry		sym, syn	union or together
gingiv/o	gum		syndrom/o	running together
glauc/o	grey
gli/o	glue		tac	order, arrange
globin, gobulin	protein		tachy	fast
gloss/o	tongue		taxis	muscular coordination
gluc/o, glyc/o	sugar, sweetness		tempor/o	temporal
gonad/o	sex organs		ten/o, tend/o	tendon
gran	grain, particle		tens	stretch
graph, graphy	instrument for recording		tetra-	four
gravida	pregnancy		thalam/o	chamber
gyn/o	woman, female		thel/o	nipple
			thermo-	heat
hem/o, hemat/o	blood		thorax	chest
hemi-	half		thromb/o	clot
hepat/o	liver		-tocia	childbirth, labor
hered/o, heredit/o	inherited, inheritance		-tome	instrument to cut
heter/o	different		-tomy	incision, section
hidr/o	sweat		ton/o	tension, pressure
hist/o	tissue		toxic/o	poison
homo-	same		trans-	across, through
humer/o	humerus		taumat/o	injury
hydr/o	water		tri	three
hyper-	above average		trich/o	hair
hypo-	below average		troph-	stimulate
hyster/o	uterus, womb		-trophy	nourishment, development
			-tropia	turning
-ia	state or condition		-tropin	stimulate
iatr/o	medicine, physician		-tripsy	crushing (intentionally)
ichthy/o	dry, scaly		typmpan/o	eardrum
idi/o	self produced, unknown
im, in	not		ultra-	beyond, excess
infra, inder,	below, beneath		ungu/o	nail
inter-	between		uni-	one
intra-	in, within		urtic/o	nettle, stinging nettle, hives
-ion	process
Ipsi-	same		ven/o	vein
irid/o	iris		ventr/o	belly, bellyside
is/o equal			vesic/o	bladder
ischi/o	ischium		viscer/o	internal organs, abdominal
-itis	inflammation		vit-	life
kal/i	potassium		xanth/o	yellow
kary/o	nucleus
kerat/o	hard, horny, cornea		zyg	union, join
kineisi/o	movement
kyph/o	hump
lab/i	lip
labyrinth/o	inner ear, maze
lacer/o, lacerat/o	torn, mangled
lacrim/o	tear
lact/o	milk
lapar/o	abdomen
later/o	side
lei/o	smooth
leuc/o, leuk/o	white
lepsy	seizure
lingu/o	tongue
lip/o	fat
lith-	stone
lithiasis	presence, condition, formation of calculi
-logy	science of
-ly	loose, dissolve