A fight using fists; a boxing match or brawl.
From fist + cuff (archaic word for 'a blow' or 'to hit'). Emerged in the 1600s as a playful, slightly ridiculous-sounding term for fighting.
Fisticuffs is probably the silliest-sounding word in English for something violent—it sounds like it should be describing a comedy skit rather than an actual fight. That playfulness is intentional; it's one of those words people use to make something rough sound more genteel or humorous.
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