To mutter is to speak or chatter in a low voice or under your breath in a way that is hard to hear, or to spread rumors, or speak about someone unofficially.(verb)
See mutter in Webster's New World College Dictionary
Origin: ME moteren, akin to Ger muttern, ult. < IE echoic base *mu- (see mope) > L muttire
See mutter in American Heritage Dictionary 4
verb mut·tered, mut·ter·ing, mut·ters verb, intransitive
Origin: Middle English muttren
Origin: , possibly from Latin muttīre.
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