1590s, variant of Middle English gonfanon (c.1300), from Old French gonfanon "knight's pennon" (12c.), from Old High German guntfano "battle flag," from a Proto-Germanic compound of *gunthjo "war, battle" (from PIE *gwhen- "to strike, kill;" see bane) + *fano "banner" (compare Gothic fana "cloth;" see fane). Cognate with Old English guþfana, Old Norse gunnfani. Change of -n- to -l- by dissimilation.