early 15c., "small piece of glittering metal," diminutive of spang "glittering ornament, spangle," probably from Middle Dutch spange "brooch, clasp," cognate with Old English spang "buckle, clasp," from Proto-Germanic *spango, from an extended form of the root of span, v..

1540s, "cover with spangles," from spangle, n.. Intransitive meaning "glitter, glisten" is from 1630s. Related: Spangled; spangling.