a.

1. 隐秘不明的，别有用心的
   There was no ulterior motive in his proposal.

   他的建议里没有不可告人的动机。

2. 在那边的；较远的
3. 日后的，将来的；进一步的
   I want to know what is our ulterior action.

   我想要知道下一步的行动是什么。

adj.

1. other than what is obvious or admitted:
   she had some ulterior motive in coming.
2. beyond what is immediate or present.