reverb (n.)

late 14c., reverberacioun, "reflection of light or heat, repercussion of air," from Old French reverberacion "great flash of light; intense quality" and directly from Medieval Latin reverberationem (nominative reverberatio), noun of action from past-participle stem of Latin reverberare "beat back, strike back, repel, cause to rebound." This is from from re- "back" (see re-) + verberare "to strike, to beat," from verber "whip, lash, rod," related to verbena "leaves and branches of laurel" (from *werb- "to turn, bend," from PIE root *wer- (2) "to turn, bend"). The sense of "an echo" is attested from 1620s.