Introduction to Medical Terminology 'O' Prefixes, Word Roots, and Suffixes
-osis
abnormal condition, disease
ob-
against
-orexia
appetite
occipit/o
back of skull, occiput
opisth/o
backward
oss/e, oss/i, oste/o, ost/o
bone
-ostosis
condition of bone
oxid/o
containing oxygen
opercul/o
cover or lid
-otomy
cutting, surgical incision
-otia
ear condition
ot/o
ear, hearing
o/o, oo/o
egg
ovul/o
egg
ov/i, ov/o
egg, ovum
olecran/o
elbow, olecranon
ocul/o
eye
ophthalum/o
eye, vision
opt/i, opt/o, optic/o
eye, vision
onych/o
fingernail or toenail
-ose
full of, pertaining to, sugar
occult/o
hidden, concealed
-one
hormone
-oid
like, resembling
-ole
little, small
obsetetr/i, obstetr/o
midwife, one who stands to receive
os-
mouth, bone
or/o
mouth, oral cavity
obes/
obese, extremely fat
oblongat/o
oblong, elongated
-opaque
obscure
oment/o
omentum, fat
orbit/o
orbit, bony cavity or socket
organ/o
organ
ossicul/o
ossicle (small bone)
oophor/o
ovary
ovari/o
ovary
ox/i, ox/o, ox/y
oxygen
-oxia
oxygen condition
oper/o, operat/o
perform, operate, work
-ory
pertaining to
osm/o
pushing, thrusting
olig/o
scanty, few
opac/o, opacit/o
shaded, dark, impenetrable to light
om/o
shoulder
occlud/o, occlus/o
shut, close up
obliqu/o
slanted, sideways
-osmia
smell, odor
olfact/o
smell, sense of smell
-ologist
specialist
orth/o
straight, normal, correct
oxysm/o
sudden
-ostomy
surgically creating an opening
orgasm/o
swell, be excited
oxy-
swift, sharp, acid
orch/o, orchid/o, orchi/o
testicles, testis, testes
-ology
the science or study of
odont/o
tooth
onc/o
tumor
-oma
tumor, neoplasm
omphal/o
umbilical cord, the navel
-opia
vision condition
-opsia, -opsis, -opsy
vision, view of