1670s, "showy brilliance," from Fr. éclat
"splinter, fragment" (12c.), also "flash of brilliance," from eclater
"burst out, splinter," from O.Fr. esclater
, of uncertain origin, perhaps from a W.Gmc. word related to slit
or to O.H.G. sleizen
"tear to pieces; to split, cleave." Extended sense of "conspicuous success" is first recorded in English in 1741.