Late 15th century; earliest use found in William Caxton (1415x24–1492), printer, merchant, and diplomat. From Anglo-Norman resplendur, resplendor, resplendour, Anglo-Norman and Middle French resplendeur from resplendre + -ur, -our, probably after classical Latin splendor (which the French word and its Romance cognates frequently render as a translation equivalent). Compare Old Occitan resplandor, Catalan resplendor, Spanish resplendor, Portuguese resplendor, Italian risplendore, †resplendore, †resplandore.

Late 19th century; earliest use found in Charles Godfrey Leland (1824–1903). From re- + splendour.