Rumbling

Adjective

 * 1) Deep and slow sounding.
 * His rumbling voice fit the solemn occasion.

Noun

 * 1) The sound of complaint.
 * The rumblings of the masses precedes the crumbling of the state.

Verb
rumbling

Thesaurus
boom, booming, cannonading, echo, echoic, echoing, fulminating, growl, growling, grumble, grumbling, lingering, pealing, persistent, reboant, reboation, rebound, rebounding, reecho, reechoing, repercussive, resound, resounding, reverberant, reverberating, reverberation, reverberatory, roaring, rolling, rumble, sounding, thunder, thundering, thunderlike, thunderous, thundery, tonitruant, tonitruous, undamped, volleying