This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

verb-intransitive. To speak indistinctly in low tones.

verb-intransitive. To complain or grumble morosely.

v. To utter or say in low indistinct tones.

n. A low grumble or indistinct utterance.

n. A repressed or obscure utterance; an instance of muttering.

n. peas

v. To utter words, especially complaints or angry expressions, indistinctly or with a low voice and lips partly closed; to say under one's breath.

v. To speak softly and incoherently, or with imperfect articulations.

v. To make a sound with a low, rumbling noise.

verb-intransitive. To utter words indistinctly or with a low voice and lips partly closed; esp., to utter indistinct complaints or angry expressions; to grumble; to growl.

verb-intransitive. To sound with a low, rumbling noise.

v. To utter with imperfect articulations, or with a low voice.

n. Repressed or obscure utterance.

To utter words in a low tone and with compressed lips, as in complaint or sullenness; murmur; grumble.

To emit a low rumbling sound.

To utter with imperfect articulation, or in a low murmuring tone.

n. A murmur or murmuring; sullen or veiled utterance.

v. talk indistinctly; usually in a low voice

n. a low continuous indistinct sound; often accompanied by movement of the lips without the production of articulate speech

n. a complaint uttered in a low and indistinct tone

v. make complaining remarks or noises under one's breath

"I don't think that what "W" has to mutter is worth much."

muttered    muttering    mutters   

mouth    verbalise    speak    verbalize    utter    talk    sound    complaint    sound off    kick   

muttered    muttering    mutter paneer   

grumble    growl    mumble    murmur    mumblement   

Nutter    Sutter    aflutter    butter    clutter    cutter    flutter    gutter    hutter    nutter   

mutterings    grunt    growl    mumble    glower    rustlings    insufflation    grimace