Prefixes
The ability to break down medical terms into separate components or to recognize a complete word depends on the mastery of the combining forms (a stem or root with an "o" attached), roots or stems that appear in medical terms, and prefixes and suffixes that alter or modify meaning and usage of a term.
Prefixes, the most frequently used elements in the formation of Greek and Latin words, consist of one or more syllables (prepositions or adverbs) placed before words or roots to show various kinds of relationships. They are never used independently, but when added before verbs, adjectives, or nouns, they modify the meaning. Most prefixes are a part of words in ordinary speech and do not refer specifically to medical or scientific terminology, but many occur frequently in medical terminology. The prefixes used in medical terminology follow.
Prefix | Meaning | Examples |
a-,
an- |
Without, not lack of |
Aphasia (without speech)
Anemia (lack of blood) |
ab-ab- | Away from |
Abductor (leading away from)
Aboral (away from mouth) |
ad- | To, toward, near |
Adductor (leading toward)
Adrenal (near the kidney) |
ambi-,
ampho- |
Both |
Ambidextrous (ability to use hands equally)
Amphogenic (producing young both sexes) |
amphi- | On both sides, double |
Amphibious (living both on land and in water)
Amphithymia (dual mental state of depression and elation) |
ana- | Up, toward, apart |
Anatomy (to cut apart)
Anacatharis (vomiting up) |
ante- |
Before, in front of,
forward |
Antecubital (before elbow)
Anteflex (to bend forward) |
anti- | Against, opposing |
Anticarious (against cavities)
Antisepsis (against infection) |
ap-,
apo- |
Separation from,
derived from |
Apobiosis (death of a part)
Apocleisis (aversion to food) |
aut-,
auto- |
Self |
Autoanalysis (self analysis)
Autoerotism (sexual self love) |
bi- | Two, double, twice |
Biarticulate (double joint)
Bifocal (two foci) |
cata- |
Down, under, lower,
against |
Catabolism (breaking down)
Catalepsy (reduced movement) |
circum- | Around |
Circumflex (winding around)
Circumarticular (around joint) |
co-,
* com-, Ü con- |
With, together |
Commissure (coming together)
Conductor (leading together) |
contra- | Opposed, against |
Contralateral (opposite side)
Contraception (prevention of conception) |
de- | Down, from |
Dehydrate (remove water from)
Decay (break down) |
di- | Two, twice |
Dicephalous (two headed)
Dichromic (having two colors) |
dia- |
Between, through, apart,
across, completely |
Diaphragm (wall across)
Diapedesis (ooze through) Diagnosis (complete knowledge) |
dis- | Apart or free from |
Disinfection (infection)
Disarticulation (separation at a joint) Dissect (cut apart) |
dys- | Difficult, bad, painful |
Dyskinesis (difficult motion)
Dyspepsia (bad digestion) Dyspareunia (painful coitus) |
e-,
ec-, ex- |
Out of, from, away from |
Enucleate (remove whole from)
Exostosis (outgrowth of bone) Ectopic (out of place) Ectal (on the surface) |
ect-,
ecto-, exo- |
Outer, outside,
situated on |
Ectoderm (outer skin)
Ectocystic (outside of cell) Exogenic (originating outside) |
em-,
** en- |
In |
Empyema (pus in)
Encranial (in the cranium) |
end-,
endo-, ent-, ento- |
Within, inner |
Endaural (within the ear)
Endocranial (within cranium) Entiris (inner eye color) Entocele (internal hernia) |
ep-,
epi- |
Upon, on, over |
Epicostal (upon a rib)
Epidermis (outer skin layer) Eponychia (infection over the nail bed) |
eu- |
Normal, good, well,
healthy |
Eucrasia (normal health)
Eublastic (healing well) |
extra-,
extro- |
Outside of, beyond,
outward |
Extraoral (outside of mouth)
Extroversion (turning inside out) |
hemi- | Half |
Hemiepilepsy (epilepsy on one side of body)
Hemilingual (half of tongue) |
hyper- |
Excessive, above,
beyond |
Hyperactive (overactive)
Hypertension (above normal blood pressure) |
hyp-,
hypo- |
Under, deficient, beneath |
Hypalgia (reduced pain sense)
Hypothyroidism (deficiency of thyroid activity) |
im-,
ÜÜ in- |
In, into, within |
Implant (insert into)
Injection (forcing fluid into) |
im-,
Ü in- |
Not |
Immature (not mature)
Involuntary (not voluntary) |
infra- | Below, beneath |
Infraorbital (beneath eye)
Infracostal (below a rib) |
inter- | Between |
Intercostal (between ribs)
Internodal (between nodes) |
intra- | Within |
Intracardiac (within heart)
Intraocular (within the eye) |
intro- | Into, within |
Introversion (turning inward)
Introrsus (turned in) |
mes-,
meso- |
Middle |
Mesencephalon (midbrain)
Mesonasal (middle of nose) |
meta- | Change, beyond |
Metachrosis (color change)
Metabasis (disease changes) |
micr-,
micro- |
Small |
Micracoustic (faint sounds)
Microbe (minute organism) |
mult-,
multi- |
Many |
Multiangular (many angles)
Multiform (many shapes) |
neo- | New, recent |
Neoblastic (new tissue growth)
Neonatal (newborn) |
pan- | All, entire |
Panacea (cure-all)
Pantalgia (entire body pain) |
para- | Beside, beyond, after |
Paracardiac (beside the heart)
Paracyesis (pregnancy outside the uterus) |
per- | Through, excessive |
Permeable (may pass through)
Peracute (excessively sharp) |
peri- | Around |
Periosteum (around bone)
Peribulbar (around eye bulb) |
poly- | Many, much, excessive |
Polycystic (many cysts)
Polydipsia (excessive thirst) |
post- | After, behind |
Postoperative (after surgery)
Postocular (behind eye) |
pre-,
pro- |
Before, in front of |
Prenatal (before birth)
Project (throw forward) |
pseud-,
pseudo- |
False |
Pseudarthrosis (false joint)
Pseudocyesis (false pregnancy) |
re- | Again, backward |
Reflex (bend back)
Regurgitation (vomiting) |
retro- | Backward, behind |
Retrograde (going backward)
Retrolingual (behind tongue) |
semi- | Half |
Semiconscious (partly aware)
Seminormal (half normal) |
sub- | Under, beneath |
Subcutaneous (under the skin)
Subungual (under the nail) |
super-,
supra- |
Above, superior, excess |
Superactivity (overactivity)
Suprarenal (above kidneys) |
sym-,
** syn- |
Together, with |
Symmelia (fusion of limbs)
Synclinal (bent together) |
trans- | Across, through |
Transection (cut across)
Transaortic (through aorta) |
ultra- | Beyond, excess |
Ultravirus (very small virus)
Ultrasonic (beyond upper limit of human hearing) |
* co- | before a vowel | Ü com- | before b, m, and p |
** em- | before b, m, and p | ÜÜ im- | before b, m, and p |
*** sym- | before b, m, p, and ph |
REFERENCE
Austrin M.G. and H.E. Austrin. 1991. Learning Medical Terminology . ed. 7. Mosby, St. Louis.
IFU-10454[A]