打死老虎

打死老虎

Literally means:

beat a dead tiger

Actually means:

Although aware that the tiger is dead and it is unnecessary to beat it, a person deliberately beats it.

Metaphorically, it means attacking people who are no more powerful or influential. Sometimes it implies that it is unnecessary or rather pretentious to do so. Often derogatory.

老虎已经死了，明明知道没有再打了，却偏偏还要打。

比喻抨击或打击已经失去了威势或力量的人。有时含没必要这样做的意思，或者这样做有装腔作势的意思。多具有贬义色彩。