Medical Terminology: Prefixes
An educational guide to understanding prefixes in medical terms
Medical Terminology: Prefixes
An educational guide to understanding prefixes in medical terms
Introduction
Medical words often have three main parts: prefix, root, and suffix.
Each part changes the meaning of the word.
Even a small change (e.g., hyper- vs hypo-) can completely alter meaning.
Prefixes Overview
Prefixes appear at the start of medical terms.
They often describe:
• Location
• Quantity
• Condition
• Direction
AB-
Meaning: away from
Examples:
• Abnormal – away from normal
• Abduction – movement away from midline
AD-
Meaning: toward or to
Examples:
• Adhere – to stick together
• Adduction – movement toward the body
A- or AN-
Meaning: without or not
Examples:
• Anaesthesia – without sensation
• Asepsis – without infection
HYPER-
Meaning: excessive or above normal
Examples:
• Hyperglycaemia – high blood sugar
• Hyperactive – overactive
HYPO-
Meaning: below or deficient
Examples:
• Hypoglycaemia – low blood sugar
• Hypothermia – low body temperature
SUB-
Meaning: under or beneath
Examples:
• Subcutaneous – under the skin
• Sublingual – under the tongue
SUPER- or SUPRA-
Meaning: above or beyond
Examples:
• Suprapubic – above the pubic bone
• Superacute – extremely severe
DE-
Meaning: down or away from
Examples:
• Decompose – break down
• Dehydrate – remove water
ANTI- and CONTRA-
Meaning: against or opposing
Examples:
• Antibiotic – fights bacteria
• Contraception – prevents conception
CON-
Meaning: with or together
Examples:
• Congenital – born with
• Constrict – to narrow together
BRADY- and TACHY-
Meaning: slow (brady-) and fast (tachy-)
Examples:
• Bradycardia – slow heart rate
• Tachypnoea – rapid breathing
E-, EC-, ECTO-, EX(O)-, EXTRA-
Meaning: out or outside
Examples:
• Exocrine – secreting outside
• Extracellular – outside the cell
ENDO-
Meaning: within or inside
Examples:
• Endocardium – inner layer of heart
• Endotracheal – within the trachea
INTRA- and INTER-
Meaning: within (intra-) or between (inter-)
Examples:
• Intravenous – within a vein
• Intercellular – between cells
PERI-
Meaning: around
Examples:
• Pericarditis – inflammation around the heart
• Periosteum – membrane around bone
PARA-
Meaning: beside or near
Examples:
• Paramedical – beside medicine
• Parahepatic – near the liver
EPI-
Meaning: upon or over
Examples:
• Epidermis – outer layer of skin
• Epiglottis – flap over the larynx
RETRO-
Meaning: behind or backward
Examples:
• Retroflexed – bent backward
• Retrostalsis – backward movement
PRE-, PRO-, ANTE-
Meaning: before or in front of
Examples:
• Prenatal – before birth
• Prognosis – prediction of disease course
POST-
Meaning: after or behind
Examples:
• Postnatal – after birth
• Postoperative – after surgery
PER-
Meaning: through
Examples:
• Perforate – go through
• Permeable – allow passage
MAL- and DYS-
Meaning: bad, difficult, or painful
Examples:
• Dysuria – painful urination
• Malnutrition – poor nutrition