What is the meaning of the prefix ad-?

• A. Toward
• B. With
• C. Against
• D. Within

Answer: (A)

Ad- signals movement toward or toward a point of reference. It comes from Latin ad meaning toward, which is why it appears in many English words that describe approaching or becoming toward something—like adjacent (placed near), adhere (to stick toward), or advance (move toward a goal). That directional sense is what the question is testing, so the best answer is toward.

The other ideas don’t fit because they come from different prefixes: a prefix meaning with is often seen as com-/con- or syn-/sym-, a prefix meaning against is contra-, and a prefix meaning within is intra-.