brass knuckles is a noun meaning "(used in the plural) a small metal weapon; worn over the knuckles on the back of the hand". It carries one recorded sense.
(used in the plural) a small metal weapon; worn over the knuckles on the back of the hand
plural
Definitions, synonyms and semantic relations for brass knuckles come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.