knuckle up

Verb

Meaning

(informal, chiefly African-American Vernacular) To clench one's fist(s) as though in preparation for a fight.

(informal, by extension) To approach a problem aggressively.

Source: en.wiktionary.org

Close letter words and terms

knuckle to knuckle touch knuckle under knuckle-buster knuckle-dragging knuckle-scraper