Ep(i) means which of the following?

• A. On top of
• B. Within
• C. Red
• D. Sensation

Answer: (A)

Ep(i) is a prefix that signals location on or above something. That explains why it means “on top of.” In medical terms you’ll see it in words like epidermis, the outer skin layer literally on top of the dermis; epigastric region, an area above the stomach; and epidural space, the space above the dura mater. Because epi- denotes exterior or superior positioning, it wouldn’t convey “within” (that would be endo- or intra-), nor does it refer to color or sensation.