绚 is a bound morpheme (b.f.) meaning 'gorgeous' or 'splendid', almost always used as the first element in two-character compounds like 绚丽 (xuànlì, 'gorgeous, magnificent') and 绚烂 (xuànlàn, 'splendid, dazzling'). It describes bright, brilliant colors or visual beauty. You won't use 绚 alone in modern Chinese — it must combine with another character to form a full word.