Of or relating to the Celts; spec. of or relating to the inhabitants of central Gaul (Gallia Celtica) (see Celt, n.1 1a); (also occasionally)…

Celtic (in various senses of Celtic, adj.). Now also: somewhat Celtic in style or character.

Of or relating to the Celts considered more widely as a group including any of various ancient peoples inhabiting western Europe and the British…

Of, relating to, representing, or involving all Celts or Celtic peoples; (also) of or relating to Pan-Celticism (pan-Celticism, n.).