1
general::
Phrase(s): mutter something about someone or something
to say something softly and indistinctly about someone or something. • I heard him mutter something about being late. • Sharon is muttering something about Dave. What does she mean?, Phrase(s): mutter about someone or something
to grumble or complain about someone or something. • Are you muttering about me? What is your complaint? • Why is everyone muttering about the food here? It is excellent.
McGrawhill's American Idioms And Phrasal Verbs