Merriam-Webster Online Dictionary states the definition of fight as:
Main Entry: 1fight Pronunciation: ‘fItFunction: verbInflected Form(s): fought /‘fot/; fight·ing
Etymology: Middle English, from Old English feohtan; akin to Old High German fehtan to fight and perhaps to Latin pectere to comb — more at PECTINATE
intransitive senses
1 a : to contend in battle or physical combat; […]