To fight or argue with someone or something. Once politics are mentioned at family dinners, everyone starts doing battle. Oh, I've done battle with the principal about my curriculum many times before—I'm not worried.
See also: battle
If you join battle with someone, you decide that you will try to defeat them in an argument or contest. Carter led the challenge against the Prime Minister and now finds himself joining battle with two of the party's most admired figures. European finance ministers will join battle this weekend in a new row over who should represent the Euro on the international stage.