A prefix comes at the beginning of the word and usually modifies the meaning of the word root. Let’s see an example of how prefixes do this:
- Glycemia is a medical term that means, “presence of glucose in the blood.”
- Word Root = Glyc/o = glucose/sugar
- Suffix = -emia = present in blood
- Now let’s add a prefix to this term:
- Hyperglycemia = Excessive or above normal level of glucose/sugar present in the blood.
- Hypoglycemia = Less than normal level of glucose/sugar present in the blood.
Do you see how a prefix can change the definition of the medical term without modifying the meaning of the word root? Once attached to a medical term, they can express quantity, measurements, position, color, and much more.
The rest of this module will list common prefixes that are used in general context.
Prefix | Definition | Example |
a- | Without; Lack of | Aphagia = Lack of eating |
an- | Without; Lack of | Anesthesia = Without feeling |
ab- | From; Away from | Abduct = Movement away from the midline of the body |
ad- | Toward; Increase | Adduct = Movement toward the midline of the body |
ambi- | Both; Both sides | Ambidextrous = Ability to use both hands equally |
ante- | Before; In front | Antecubital = In front of the elbow |
anti- | Against; Opposing | Antibiotics = “Opposing life;” A substance used against microbes |
bi- | Two; Double | Bifocal = Two foci |
bio- | Life | Biology = Study of life |
brady- | Slow | Bradycardia = Slow heart rate |
chlor/o- | Green | Chlorophyll = Green pigment in plants |
circum- | Around | Circumflex = Curved around |
con- | With; Together | Congenital = Born with |
contra- | Against; Opposite | Contralateral = Opposite side |
dia- | Through; Across; Completely | Diagnosis = Complete knowledge; Knowledge through testing |
dis- | Free of; Undo; Reversal; Apart from; Separation | Dissect = To cut apart |
dys- | Bad; Difficult; Painful | Dyspnea = Difficulty breathing |
endo- | Within; Inner | Endoscopy = To examine within the body |
epi- | Upon; Over | Epidermis = Outer layer of skin |
hemi- | Half | Hemiplegia = Paralysis of half of the body |
hetero- | Different | Heterozygous = Two different forms of a gene |
homo- | Same | Homogeneous = Same composition/structure throughout |
hyper- | Excessive; Above normal | Hypertension = High blood pressure |
hypo- | Under; Below; Less than normal | Hypothermia = Below normal temperature |
inter- | Between | Intercostal = Between the ribs |
intra- | Within | Intravenous = Within the vein |
jaund/o- | Yellow | Jaundice = Yellowing of the skin |
meta- | Beyond; After | Metacarpal = Bones beyond the wrist |
para- | Near; Beside; Beyond | Paracardiac = Beside the heart |
peri- | Around | Periosteum = Around the bone |
pre- | Before; In front of | Premaxillary = In front of the Maxilla |
re- | Back; Again | Reactivate = To make active again |
retro- | Backward; Located behind | Retrolingual = Behind the tongue |
semi- | Half | Semiconscious = Half conscious |
tachy- | Fast; Rapid | Tachycardia = Fast heart rate |