of persons, 'dressed up, decked out in finery,' late 14c. of colors, etc., 'shining, glittering, gleaming, bright, vivid,' late 14c.
Of things, 'sumptuous, showy, rich, ornate,' mid-14c. Meaning 'stately and beautiful splendid and showily dressed' is from early 14c. Ultimate origin disputed perhaps from Frankish *gahi (related to Old High German wahi 'pretty'), though not all etymologists accept this. compare Old Spanish gayo, Portuguese gaio, Italian gajo, probably French loan-words).
as a surname, Philippus de Gay), from Old French gai 'joyful, happy pleasant, agreeably charming forward, pert light-colored' (12c. Late 14c., 'full of joy, merry light-hearted, carefree ' also 'wanton, lewd, lascivious' (late 12c.
