MUTTERING
grumble, grumbling, murmur, murmuring, mutter, muttering
(noun) a complaint uttered in a low and indistinct tone
mutter, muttering, murmur, murmuring, murmuration, mussitation
(noun) a low continuous indistinct sound; often accompanied by movement of the lips without the production of articulate speech
Source: WordNet® 3.1
Verb
muttering
present participle of mutter
Noun
muttering (plural mutterings)
Something that is muttered.
A rumour.
Synonyms
• (something muttered): mumblage
Source: Wiktionary
MUTTER
Mut"ter, v. i. [imp. & p. p. Muttered; p. pr. & vb. n. Muttering.]
Etym: [Prob. of imitative origin; cf. L. muttire, mutire.]
1. To utter words indistinctly or with a low voice and lips partly
closed; esp., to utter indistinct complains or angry expressions; to
grumble; to growl.
Wizards that peep, and that mutter. Is. viii. 19.
Meantime your filthy foreigner will stare, And mutter to himself.
Dryden.
2. To sound with a low, rumbling noise.
Thick lightings flash, the muttering thunder rolls. Pope.
Mut"ter, v. t.
Definition: To utter with imperfect articulations, or with a low voice; as,
to mutter threats. Shak.
Mut"ter, n.
Definition: Repressing or obscure utterance.
Source: Webster’s Unabridged Dictionary 1913 Edition