I. bri-ˈthä-nik adjective
Etymology: Welsh Brython Briton, Britons (from British Celtic * britton- ) + -ic (I)
Date: 1884
: of, relating to, or characteristic of the division of the Celtic languages that includes Welsh, Cornish, and Breton
II. noun
Date: 1884
: the Brythonic branch of the Celtic languages — see Indo-European languages table