briar1Pronunciation: /brʌɪə/ (also brier)Translate briar | into Italian Definition of briar noun any of a number of prickly scrambling shrubs, especially a wild rose: [as modifier]:a briar patchGenus Rosa, family Rosaceae: several species, including the Eurasian sweet briar (R. rubiginosa) Derivatives briary adjective Origin: Old English brǣr, brēr, of unknown originbriar in other Oxford dictionaries Definition of briar in the US English dictionary