mumbling has definitions from the fields of linguistics,phonetics
1
[ noun ] (linguistics,phonetics) indistinct enunciation

Related terms

enunciation mumble

2
[ adjective ] speaking low and indistinctly

Synonyms

muttering

Examples

"a mumbling parson stood beside the dying man" "muttering crowds of onlookers"

Related terms

speaking

3
[ noun ] ineffectual chewing (as if without teeth)

Synonyms

gumming

Related terms

chew mumble

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