grumbling

Noun	1.	grumbling - a loud low dull continuous noise; "they heard the rumbling of thunder" Synonyms: grumble, rumble, rumbling
	2.	grumbling - a complaint uttered in a low and indistinct tone Synonyms: grumble, murmuring, mutter, muttering, murmur
Adj.	1.	grumbling - continuous full and low-pitched throbbing sound; "the rumbling rolling sound of thunder" Synonyms: rumbling
	2.	grumbling - muttering discontentedly; "the grumbling boarders requested a meeting with the cook"

full, rumbling