(n.) The act of reverberating; especially, the act of reflecting light or heat, or reechoing sound; as, the reverberation of rays from a mirror; the reverberation of rays from a mirror; the reverberation of voices; the reverberation of heat or flame in a furnace.

acknowledgment action and reaction answer answering antiphon automatic reaction autonomic reaction back answer back talk backchat boom booming bounceback comeback echo evasive reply growl growling grumble grumbling predictable response reaction ready reply reboation rebound receipt reecho reflection reflex reflex action refluence reflux rejoinder repartee replication reply repost rescript rescription resound resounding respondence response responsion responsory retort retroaction return revulsion riposte rise rumble rumbling short answer snappy comeback thunder thundering unthinking response witty reply witty retort yes-and-no answer