a branch of the Indo-European family of languages that includes Gaelic, Welsh, and Breton, still spoken in parts of Scotland, Ireland, Wales, and Brittany. Modern Celtic is divided into the Brythonic (southern) and Goidelic (northern) groups
of, relating to, or characteristic of the Celts or the Celtic languages
1656, of archaeology or history, from Fr. Celtique or L. Celticus "pertaining to the Celts (see Celt). Of languages, from 1707; of other qualities, 19c. Celtic twilight is from Yeats's name for his collection of adapted Irish folk tales (1893).