rumbling

from WordNet (r) 3.0 (2006)

rumbling
    adj 1: continuous full and low-pitched throbbing sound; "the
           rumbling rolling sound of thunder" [syn: {grumbling},
           {rumbling}]
    n 1: a loud low dull continuous noise; "they heard the rumbling
         of thunder" [syn: {rumble}, {rumbling}, {grumble},
         {grumbling}]

from The Collaborative International Dictionary of English v.0.48

Rumbling \Rum"bling\,
   a. & n. from {Rumble}, v. i.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

40 Moby Thesaurus words for "rumbling":
      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

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