Prefixes in Medical Terminology

III: Prefixes in Medical Terms

Definition of Prefix:
- A prefix consists of one or two syllables placed before a word to modify its meaning.
- These syllables are often derived from prepositions or adverbs.

Common Prefixes and Their Meanings

ab- (L): from, away from
- Examples:
  - abductor:
  - Analysis: ab- (away from) + ductor (that which draws)
  - Definition: That which draws away from a common center, as a muscle.
  - abnormal:
  - Analysis: ab- (away from) + norma (rule)
  - Definition: Away from or not corresponding to rule.
  - abruptio placentae:
  - Analysis: ab- + ruptere (break) + placenta (a flat cake)
  - Definition: A tearing away from or the premature detachment of a normally situated placenta.
a, an (G): without, not
- Examples:
  - anesthesia:
  - Analysis: an- (without) + aesthesis (sensation)
  - Definition: Loss of sensation.
  - apnea:
  - Analysis: a- (without) + pnoc (breath)
  - Definition: Temporary absence of respiration.
  - asthenia:
  - Analysis: a- (without) + sthenos (strength)
  - Definition: Debility, loss of strength.
  - atresia:
  - Analysis: a- (without) + tresis (a perforation)
  - Definition: Absence or closure of a normal opening or passage.
ad- (L): adherence, increase, near, toward
- Examples:
  - adductor:
  - Analysis: ad- (toward) + ductor (that which draws)
  - Definition: That which draws toward a common center.
  - adrenal:
  - Analysis: ad- (near) + ren (kidney)
  - Definition: A ductless gland above the kidney.
  - adhesion:
  - Analysis: ad- (to stick) + nectere (to tie, to bind)
  - Definition: Abnormal joining of surfaces to each other.
  - adnexa:
  - Analysis: Ad- (to) + nex (to tie)
  - Definition: Accessory parts; for example, adnexa uteri.
ante- (L): before
- Examples:
  - anteflexion:
  - Analysis: ante- (forward) + flectere (to bend)
  - Definition: Forward displacement of an organ; for example, the uterus.
  - antenatal:
  - Analysis: ante- + natus (birth)
  - Definition: Before birth.
  - antepartum:
  - Analysis: ante- + partum (labor)
  - Definition: Before the onset of labor.
anti- (G): against
- Examples:
  - antisepsis:
  - Analysis: anti- (against) + sepsis (putrefaction)
  - Definition: The exclusion of putrefactive germs (germs that cause decay).
  - antitoxin:
  - Analysis: anti- + toxikon (poison)
  - Definition: A protein that defends the body against a toxin.
  - antipyretic:
  - Analysis: anti- + pyretos (fever)
  - Definition: A drug that reduces fever.
bi- (L): two, both, double
- Examples:
  - biceps:
  - Analysis: bi- (two) + caput (head)
  - Definition: Muscle of the upper arm having two heads.
  - bifurcation:
  - Analysis: bi- (two) + furca (fork)
  - Definition: A separation into two branches.
  - bilateral:
  - Analysis: bi- + latus (side)
  - Definition: Affecting both sides.
co- (L): together, with
- Examples:
  - congenital:
  - Analysis: con- (with) + genitus (born)
  - Definition: Born with a defect, hereditary.
  - connective tissue:
  - Analysis: con- + nectere (to bind)
  - Definition: Tissue which connects or binds.
  - conjunctiva:
  - Analysis: con- + junctiva (to join)
  - Definition: Mucous membrane which lines eyelids.
contra- (L): against, opposite
- Examples:
  - contraception:
  - Analysis: contra- (against) + concipere (to conceive)
  - Definition: The prevention of conception.
  - contraindication:
  - Analysis: contra- + indicare (to point out)
  - Definition: A condition antagonistic to a line of treatment.
  - contralateral:
  - Analysis: contra- + latus (side)
  - Definition: Affecting the opposite side of the body.
dys- (G): bad, difficult, painful
- Examples:
  - dysentery:
  - Analysis: dys- (painful) + enteron (intestine)
  - Definition: Inflammation of intestinal mucous membrane accompanied by pain.
  - dysemenorrhea:
  - Analysis: dys- + menses (menstruation)
  - Definition: Painful menstruation.
  - dyspepsia:
  - Analysis: dys- (bad) + pepto (to digest)
  - Definition: Imperfect digestion.
  - dysphagia:
  - Analysis: dys- + phagein (to eat)
  - Definition: Difficulty in swallowing.
  - dysphasia:
  - Analysis: dys- + phasis (speech)
  - Definition: Impairment of speech.
  - dyspnea:
  - Analysis: dys- + pnoc (breathing)
  - Definition: Labored or difficult breathing.
  - dystocia:
  - Analysis: dys- + tokos (birth)
  - Definition: Difficult labor.
  - dysuria:
  - Analysis: dys- + uron (urine)
  - Definition: Painful or difficult urination.
ec- (G): out
- Example:
  - ectopic pregnancy:
  - Analysis: ec- (out) + topos (place)
  - Definition: Gestation outside the uterine cavity.
- ecto- (G): outside
- Example:
  - ectropion:
  - Analysis: ecto- + trepo (to turn)
  - Definition: Eversion as the edge of the eyelid or the turning out of the cervical canal of the uterus.
em-, en- (G): in
- Examples:
  - empyema:
  - Analysis: em- (in) + pus (pyon)
  - Definition: Pus in a body cavity, especially in the pleural cavity.
  - encephalopathy:
  - Analysis: en- (in) + kephale (head)
  - Definition: Any disease of the brain.
endo- (G): within
- Examples:
  - endocardium:
  - Analysis: endo- (within) + kardia (heart)
  - Definition: Lining membrane of inner surface of the heart.
  - endocarditis:
  - Analysis: endo- + cardia (heart) + itis (inflammation)
  - Definition: Inflammation of the endocardium.
  - endocrine gland:
  - Analysis: endo- + krino (to secrete) + gland
  - Definition: A ductless gland in which forms an internal secretion.
  - endocrinology:
  - Analysis: endo- + crinis (gland) + logia (science)
  - Definition: The science of the endocrines, or ductless glands.
  - endometrium:
  - Analysis: endo- + metra (uterus)
  - Definition: The mucous membrane lining the inner surface of the uterus.
  - endometritis:
  - Analysis: endo- + metra + itis (inflammation)
  - Definition: Inflammation of the endometrium.
  - endoscope:
  - Analysis: endo- + skopein (to examine)
  - Definition: Tubular instrument for examining cavities through natural openings.
  - endoscopy:
  - Analysis: endo- + skopein + logia
  - Definition: Inspection of cavities by use of the endoscope.
  - endosteum:
  - Analysis: endo- + osteon (bone)
  - Definition: Membrane lining the medullary cavity of long bones.
  - endostitis:
  - Analysis: endo- + osteon + itis
  - Definition: Inflammation of the endosteum.
epi- (G): upon, at, in addition to
- Examples:
  - epidermis:
  - Analysis: epi- + derma (skin)
  - Definition: Cuticle or outer layer of the skin.
  - epigastrium:
  - Analysis: epi- + gaster (stomach)
  - Definition: Region over the pit of the stomach.
  - epiphysis:
  - Analysis: epi- + physis (a growing upon)
  - Definition: A center of ossification at both extremities of long bones.
ex- (L,G): out, away from, over
- Examples:
  - exacerbation:
  - Analysis: ex- + acerbus (harsh)
  - Definition: Aggravation of symptoms.
  - exeresis:
  - Analysis: ex- + keresis (taking)
  - Definition: Excision of any part.
  - exophthalmia:
  - Analysis: ex- + ophthalmos (eye)
  - Definition: Abnormal protrusion of the eyeballs.
  - exophthalmic goiter:
  - Analysis: ex- + ophthalmos + goiter
  - Definition: A goiter marked by protrusion of the eyeballs.
  - expectoration:
  - Analysis: ex- + spectare (to look)
  - Definition: Expulsion of mucus from the lungs.
  - exudate:
  - Analysis: ex- + sudare (to sweat)
  - Definition: Accumulation of fluid due to inflammatory condition.
hemi- (G): half
- Examples:
  - hemiglossectomy:
  - Analysis: hemi- + glossa (tongue) + ectome (excision)
  - Definition: Removal of half of the tongue.
  - hemigastrectomy:
  - Analysis: hemi- + gaster (stomach) + ectome
  - Definition: Removal of one-half of the stomach.
  - hemiplegia:
  - Analysis: hemi- + plegia (paralysis)
  - Definition: Paralysis of one-half of the body.
hyper- (G): above, excessive, beyond
- Examples:
  - hyperacidity:
  - Analysis: hyper- + acidus (sour)
  - Definition: An excess of acid in the stomach.
  - hyperadrenalism:
  - Analysis: hyper- + adrenal (kidney)
  - Definition: Excess of adrenal secretion.
  - hypercalcemia:
  - Analysis: hyper- + calx (lime) + haima (blood)
  - Definition: Excess of calcium in the blood.
  - hyperemesis gravidarum:
  - Analysis: hyper- + emesis (vomiting) + gravida (a pregnant woman)
  - Definition: Excessive vomiting during early pregnancy.
  - hyperemia:
  - Analysis: hyper- + haima (blood)
  - Definition: Congestion.
  - hyperpyrexia:
  - Analysis: hyper- + pyrexia (fever)
  - Definition: Fever above 106° F.
  - hypertension:
  - Analysis: hyper- + tensio (tension)
  - Definition: High blood pressure.
  - hypertrophy:
  - Analysis: hyper- + trophe (nourishment)
  - Definition: Increased size of an organ not due to tumor formation.
hypo- (G): below, deficient
- Examples:
  - hypochondrine region:
  - Analysis: hypo- + chondros (cartilage) + regio (area)
  - Definition: Part of abdomen beneath the ribs.
  - hypodermic injection:
  - Analysis: hypo- + derma (skin) + injectus (to throw in)
  - Definition: Injection under the skin.
  - hypoglycemia:
  - Analysis: hypo- + glycys (sugar) + haima (blood)
  - Definition: Low blood sugar.
para- (G): beside, around, near, abnormal
- Examples:
  - paracentesis:
  - Analysis: para- + kentesis (a puncture)
  - Definition: Puncture of a cavity with tapping.
  - parametrium:
  - Analysis: para- + metra (uterus)
  - Definition: Fat and connective tissue around the uterus.
  - parametritis:
  - Analysis: para- + metra + itis (inflammation)
  - Definition: Inflammation of the parametrium.
  - paranephritis:
  - Analysis: para- + nephros (kidney) + itis
  - Definition: Inflammation of suprarenal capsules; of connective tissue about the kidney.
  - paranoia:
  - Analysis: para- + nous (mind)
  - Definition: Mental disease marked by systematized delusions of persecution.
parathyroid:
- Analysis: para- + thyreos (shield) + eidos (form)
- Definition: Ductless gland near the thyroid gland.
parotitis:
- Analysis: para- + ot (ear) + itis (inflammation)
- Definition: Inflammation of the parotid gland.
peri- (G): around, about
- Examples:
  - pericardium:
  - Analysis: peri- + kardia (heart)
  - Definition: The double membranous sac enclosing the heart.
  - pericarditis:
  - Analysis: peri- + kardia + itis
  - Definition: Inflammation of the pericardium.
  - perimetrium:
  - Analysis: peri- + metra (uterus)
  - Definition: Peritoneum covering the uterus.
  - perimetritis:
  - Analysis: peri- + metra + itis
  - Definition: Inflammation of the peritoneum covering the uterus.
  - periosteum:
  - Analysis: peri- + osteon (bone)
  - Definition: The membrane that invests and nourishes the bone.
  - periostitis:
  - Analysis: peri- + osteon + itis
  - Definition: Inflammation of the periosteum.
pre- (L): before, in front of
- Examples:
  - precancerous:
  - Analysis: pre- + cancer (crab)
  - Definition: Before the development of carcinoma.
  - precordium:
  - Analysis: pre- + cor (heart)
  - Definition: Region over the heart.
  - preeclampsia:
  - Analysis: pre- + eclampsia (a major toxemia during pregnancy)
  - Definition: Eclampsia before delivery.
  - prepantellar bursitis:
  - Analysis: pre- + patella (kneecap) + bursa (sac) + itis
  - Definition: Inflammation of the bursa in front of the patella (Housemaid's knee).
  - presentation:
  - Analysis: pre- + sent (placing)
  - Definition: Manner of the fetus presenting itself at the cervix.
pro- (L, G): in front of, before, forward
- Examples:
  - procidentia:
  - Analysis: pro- + cidentia (a falling)
  - Definition: A complete prolapse especially of the uterus.
  - prognosis:
  - Analysis: pro- + gnosis (a knowing)
  - Definition: Prediction of end of disease.
  - prolapse:
  - Analysis: pro- + lapesus (slide)
  - Definition: A downward displacement of an organ, such as the rectum or the uterus.
retro- (L): backward, behind, back of
- Examples:
  - retroflexion:
  - Analysis: retro- + flexio (a bending)
  - Definition: A bending or flexing backward; for example, of the uterus.
  - retrogasserian neurotomy:
  - Analysis: retro- + gasserian (pertaining to a ganglion) + neuron + tome (incision)
  - Definition: Transection of the posterior root of the retrogasserian ganglion.
  - retroperitoneal:
  - Analysis: retro- + peritoneum
  - Definition: Located behind the peritoneum.
  - retroversion:
  - Analysis: retro- + versio (a turning)
  - Definition: A state of being turned back; for example, of the uterus.
semi- (L): half
- Examples:
  - semicircular canal:
  - Analysis: semi- + circular (ring) + canal
  - Definition: One of the three canals in the labyrinth of the ear.
  - semicoma:
  - Analysis: semi- + koma (lethargy)
  - Definition: Mild degree of coma.
  - semilunar valves:
  - Analysis: semi- + luna (moon)
  - Definition: Half-moon shaped valves of the aorta and pulmonary arteries.
sub- (L): under, beneath, below
- Examples:
  - subclavicular:
  - Analysis: sub- + clavicular (a little key)
  - Definition: Beneath the clavicle (collar bone).
  - subcostal:
  - Analysis: sub- + costa (rib)
  - Definition: Beneath the ribs.
  - subcutaneous:
  - Analysis: sub- + cutis (skin)
  - Definition: Beneath the skin.
  - subinvolution:
  - Analysis: sub- + involutio (a turning into)
  - Definition: Failure of the uterus to reduce to normal size after childbirth.
  - suppuration:
  - Analysis: sub- + pur (pus) + tion
  - Definition: The process of pus formation.
super-, supra- (L): above, beyond, superior
- Examples:
  - supernatant:
  - Analysis: super- + natant (to float)
  - Definition: Floating on surface.
  - supraoccipital:
  - Analysis: supra- + occiput (back part of the skull)
  - Definition: Situated above the occiput.
  - suprapubic cystotomy:
  - Analysis: supra- + pubis (bone of pelvis) + kystis (bladder) + tome (incision)
  - Definition: Surgical opening into the bladder from above the symphysis pubis.
  - suprarenal:
  - Analysis: supra- + ren (kidney)
  - Definition: Adrenal gland above the kidney.
sym-, syn- (G): with, along, together, beside
- Examples:
  - symphysis of pubis:
  - Analysis: sym- + physis (a growing)
  - Definition: Fusion of pubic bones on midline anteriorly.
  - synarthrosis:
  - Analysis: syn- + arthrou (joint)
  - Definition: An immovable joint.
  - syndactylism:
  - Analysis: syn- + daktylos (digit, finger)
  - Definition: A fusion of two or more fingers or toes: webbing.
trans- (L): across, over
- Examples:
  - transection:
  - Analysis: trans- + sectio (cutting)
  - Definition: Incision across the long axis; cross section.
  - transfusion:
  - Analysis: trans- + fusio (a pouring)
  - Definition: Injection of the blood of one person into the blood vessels of another.
  - transurethral prostatectomy:
  - Analysis: trans- + urethra + prostatitis (prostate gland) + ektome (excision)
  - Definition: Excision of the prostate gland through the urethra.
tri- (G): three
- Examples:
  - tricuspid:
  - Analysis: tri- + cuspis (a point)
  - Definition: Having three cusps or points; tricuspid valve.
  - trifacial:
  - Analysis: tri- + facialis (facial)
  - Definition: Fifth cranial nerve.
  - trigone:
  - Analysis: tri- + gonon (a three-cornered figure)
  - Definition: A triangular space, especially that of the lower part of the urinary bladder.