Grumbling - Definition

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]
2: a complaint uttered in a low and indistinct tone [syn:
grumble, grumbling, murmur, murmuring, mutter,
muttering]