belligerent

someone who fights (or is fighting)

Waging war; carrying on war.

Latin belligerare, to fight

“One of the rare women who never pout or attitudinize, she could fling her glove gracefully--one might add, capturingly under every aspect, she was a handsome belligerent.”

— George Meredith, Complete Project Gutenberg Works of George Meredith

“The prospective enemy for Britain had shifted from a Franco-Russian alliance with many armoured cruisers to a resurgent and increasingly belligerent Germany.”