a.

1. 前面的，前部的
   The anterior part of a fish contains the head and gills.

   鱼的前部包括头和鳃。

2. 以前的；较早的[（+to）]
   ages anterior to the flood

   洪水前的时期

3. （逻辑上）在前的

adj.

1. chiefly Anatomy  & Biology  nearer the front, especially in the front of the body or nearer to the head. The opposite of posterior.
   ▸Botany  situated further away from the main stem.
2. (anterior to) formal prior to.
3. Phonetics  pronounced with an obstruction located in front of the palato-alveolar region of the mouth, e.g. b, p, d, t.