From Late Latin 'combattere' (to fight together), from 'battuere' (to beat) — a word Latin borrowed from Gaulish Celts.
Fighting between armed forces; a struggle or contest between opposing forces or ideas.
From French 'combat' (15th century), from the verb 'combattre' (to fight together), from Late Latin 'combattere,' composed of 'com-' (together, with) and 'battere' (variant of 'battuere,' to beat, to strike). The Latin 'battuere' is believed to be borrowed from a Gaulish or Celtic source, as it has no clear Indo-European etymology and several Celtic cognates exist. The 'com-' prefix in this case intensifies or implies mutual action: combat is beating together, a reciprocal exchange of blows