1. To use something as a weapon while fighting someone or something. In this usage, a noun or pronoun can be used between "fight" and "with." Those guys fight dirty—they'll fight with bike chains, knives, anything they can get their hands on. I can't believe he fought you with his bare hands and gave you such a nasty black eye.

2. To fight with someone or an animal for possession of someone or something. Look, my two friends are fighting over you, so if you don't like either of them, say something now and spare us the drama. I think some dogs are out there fighting with each other over scraps.