What are the most common prefixes in medical terminology?

Common medical prefixes include hyper meaning above normal, hypo meaning below normal, tachy meaning fast, brady meaning slow, poly meaning many, oligo meaning few, dys meaning difficult or painful, a or an meaning without, anti meaning against, peri meaning around, endo meaning within, epi meaning above or upon, and inter meaning between. Prefixes attach to the beginning of a root word to modify its meaning. For example, tachycardia means fast heart rate, bradycardia means slow heart rate, and hyperglycemia means high blood sugar. Learning prefixes allows you to interpret thousands of terms.