effulgent (adj.)youdaoicibaDictYouDict[effulgent 词源字典]
1738, back-formation from effulgence, or else from Latin effulgentem (nominative effulgens), present participle of effulgere "to shine out, gleam forth," from ex "out" (see ex-) + fulgere "to shine" (see bleach (v.)). Related: Effulgently.[effulgent etymology, effulgent origin, 英语词源]
flare (v.)youdaoicibaDictYouDict
1540s, "spread out" (hair), of unknown origin, perhaps from Scandinavian or from Dutch vlederen. Meaning "shine out with a sudden light" is from 1630s. The notion of "spreading out in display" is behind the notion of "spreading gradually outward" (1640s). Related: Flared; flaring.