not needed or wanted, or more than is needed or wanted

I thought a lot of the violence in the movie was totally unnecessary. 我觉得这部电影中有很多暴力场面是完全没有必要的。

The idea is to kill the animal as quickly as possible without causing unnecessary suffering. 该主张是要尽快杀死动物，不致引起不必要的痛苦。

An offensive remark or action that is unnecessary could have been avoided.

He just humiliated her in front of everyone - it was so unnecessary. 他就在众人面前羞辱她——这太不合适了。