- (transitive, intransitive) To speak unintelligibly or inaudibly; to fail to articulate.
- Please try not to mumble so I can hear you better.
- To chew something gently with closed lips.
- See also Thesaurus:mutter
to speak unintelligibly
mumble (plural mumbles)
- A quiet or unintelligible vocalization; a low tone of voice.
- All I could hear was a mumble from the next room.
- He spoke in a barely comprehensible mumble.