Medical Terminology Prefixes: Uni-, Contra-, Color

• A prefix is a word part placed before the word root to modify its meaning.

Uni-lateral

• Uni- means "one" or "affecting one side".
• Uni-lateral refers to affecting one side.
• Uni-lateral hearing loss is hearing loss in one ear.
• This hearing loss may result from noise exposure, infection, or neuroma.

Contra-lateral

• Contra- means "opposite" or "affecting the other or opposite side".
• Contra-lateral refers to affecting the opposite side.
• Each cerebral hemisphere's motor area mainly controls movements on the body's contra-lateral (opposite) side.
• Prefixes usually indicate colors, timings, location/position, size/degree, number/measurement, direction/condition, or negation.

Prefixes Indicating Color

• Erythr/o indicates red.
  • Example: Erythrocyte means red blood cell.
• Leuk/o indicates white or colorless.
  • Example: Leukemia is cancer of white blood cells.
• Melan/o indicates black or dark.
  • Example: Melanin is the dark pigment coloring hair and skin.
• Xanth/o indicates yellow.
  • Example: Xanthoma is a yellow growth on the skin.
• Cyan/o indicates blue.
  • Example: Cyanosis is a bluish discoloration of the skin due to lack of oxygen.

Prefixes Indicating Timing

• Pre- means "before".
  • Example: Preoperative means before the operative period.
• Intra- means "during".
  • Example: Intraoperative means during the operative period.
• Post- means "after".
  • Example: Postoperative means after the operative period.
• Peri- means "around".
  • Example: Perioperative means around the operative period.
• Ante- means "before".
  • Example: Antepartum means before the delivery of the baby.

Prefixes Indicating Timing/Position

• Intra- means "in, within"
• Example: Intra-muscular

Prefixes Indicating Size

• Micro- means "small".
  • Example: Microcyte means very small cell.
• Macro- means "big".
  • Example: Macrocyte means big cell.
• Mega- means "large".
  • Example: Megacolon means enlarged colon.

Prefixes Indicating Numbers

• mon/o- means one, e.g. monocular = having one eyepiece or only affecting one eye
• uni- means one e.g. unite = form into one part
• hemi- means half, one side e.g. hemisphere = one-half of a rounded structure
• semi- means half, partial, e.g. semiconscious = not fully conscious
• bi- means two, twice e.g. binary = made up of two parts
• di- means two, twice e.g. diatomic = having two atoms
• dipl/o- means double e.g. diplococci = round bacteria that grow in groups of two
• tri- means three e.g. tricuspid = having three points or cusps
• quadr/i- means four e.g. quadruplet = one of four babies born together
• tetra- means four e.g. tetralogy = a group of four
• multi- means many e.g. multicellular = consisting of many cells
• poly- means many, much e.g. polymorphous = having many forms (morpho)

Prefixes Indicating Degree

• Hyper- means "over, excess, abnormally high, increased".
  • Example: Hyperthermia means high body temperature.
• Hypo- means "under, below, abnormally low, decreased".
  • Example: Hypothermia means low body temperature.
• Olig/o- means "few, scanty".
  • Example: Oliguria means reduced urine output.
• Pan- means "all".
  • Example: Pandemic is a disease affecting an entire population.

Prefixes Indicating Direction

• ab- means away from, e.g. abduct = to move away from the midline
• ad- means toward, near, e.g. adduct = to move toward the midline
• per- means through, e.g. percutaneous = through the skin
• trans- means through, e.g. transection = cut (sectioned) through or across

Prefixes Indicating Negative

• a-, an- means not, without, lack of, absence, e.g. Anesthesia = absence of sensation
• anti- means against, e.g. antiseptic = agent used to prevent infection
• contra- means against, opposite, opposed, e.g. contradicted = against recommendations, not advisable

Lesson Check Examples

• Pericardium refers to a fibrous sac around the heart, also called the pericardial sac.
• Anti-biotic: "anti-" means against and "biotic" comes from the Greek word "bios" meaning life.
  • An antibiotic is a substance that works against life, specifically bacteria growth.
• Hypo-ox-ia: "Hypo-" means insufficient or low, "-ox-" refers to oxygen, and "-ia" is a suffix for a condition or state.
  • Therefore, hypoxia means an insufficient oxygen condition.

Assignment

• The journal article title is "Peri-operative anesthetic management of women with obesity".
• The journal is Best Practice & Research Clinical Obstetrics & Gynaecology.
• The authors include Hon Sen Tan and Ashraf S. Habib.