Synonyms: grumble, grumbling, murmur, murmuring, mutter, muttering
Definition: a complaint uttered in a low and indistinct tone
Similar words: complaint
Definition: an expression of grievance or resentment
Synonyms: murmur, murmuration, murmuring, mussitation, mutter, muttering
Definition: a low continuous indistinct sound; often accompanied by movement of the lips without the production of articulate speech
Similar words: sound
Definition: the sudden occurrence of an audible event
Usage: the sound awakened them