maunder vs mumble

maunder is not a noun while mumble is a noun.

Word	Noun	Adjective	Verb	Adverb
maunder	No	No	Yes	No
mumble	Yes	No	Yes	No

As verbs, maunder and mumble are synonyms defined as:

Other synonyms of maunder include mussitate, mutter.

maunder (noun)	mumble (noun)
	a soft indistinct utterance

maunder (verb)	mumble (verb)
talk indistinctly; usually in a low voice	talk indistinctly; usually in a low voice
speak (about unimportant matters) rapidly and incessantly	grind with the gums; chew without teeth and with great difficulty
wander aimlessly