Which combining form means lateral, to one side?

• A. later/o
• B. cutane/o
• C. sial/o
• D. gastr/o

Answer: (A)

The main idea here is recognizing combining forms that describe location or direction. The combining form later/o means a side or toward the side, which is why it gives the meaning “lateral” (pertaining to a side) in terms like unilateral or bilateral. This form specifically carries that sense of one side or the side of the body, so it’s the correct choice for “lateral, to one side.” The other roots refer to different structures: cutane/o means skin, sial/o means saliva, and gastr/o means stomach, none of which convey the sense of side or direction.