vt.

1. 解釋，給……下定義
   Do you know who defined man as a rational animal?

   你知道是誰將人說成是有理智的動物的？

2. 規定，限定，使明確
   The powers of the courts are defined by law.

   法庭的權力是由法律規定的。

3. 確定……的界線；使……的輪廓分明
   The boundary is not clearly defined.

   這疆界沒有明確劃定。

4. 為……的特性，是……的特色[（+as）]
   Reason defines man.

   理性是人的特點。

v.

1. state or describe exactly the nature, scope, or meaning of.
   ▸give the meaning of (a word or phrase).
2. mark out the limits of.