mussitation

from WordNet (r) 3.0 (2006)

mussitation
    n 1: a low continuous indistinct sound; often accompanied by
         movement of the lips without the production of articulate
         speech [syn: {mutter}, {muttering}, {murmur}, {murmuring},
         {murmuration}, {mussitation}]

from The Collaborative International Dictionary of English v.0.48

Mussitation \Mus`si*ta"tion\, n. [L. mussitatio suppression of
   the voice, fr. mussitare to be silent, to murmur.]
   A speaking in a low tone; mumbling. [Obs.]
   [1913 Webster]

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