Definition of Afferent

Afferent: Carrying toward. A vein is an afferent vessel since it carries blood toward from the heart. An afferent nerve carries impulses toward the central nervous system. The opposite of afferent is efferent.

Definition of Ad-

Ad-: Latin prefix meaning "toward" and "in the direction of," as in adduction (movement of a limb toward the midline of the body), adhesion, and adrenal (toward the kidney).