buzz, bombilation, bombination, boom, roar, roaring, thunder, din, grumble, mumble, mutter, muttering, murmur, murmuring, murmuration, mussitation, buzzing, monotone, drone, droning, zoom, bruit, souffle
burzgimas, gausmas, bildesys, dundėjimas, dundesys, murmesys, ūžimas, zvimbesys