Main entry: grumble, grumbling, murmur, murmuring, mutter, muttering
Definition: a complaint uttered in a low and indistinct tone
Main entry: 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
Main entry: murmur, mutter, gnarl, grumble, croak
Definition: make complaining remarks or noises under one's breath
Usage: she grumbles when she feels overworked
Main entry: mumble, mussitate, mutter, maunder
Definition: talk indistinctly; usually in a low voice