manducate vs mumble

manducate is not a noun while mumble is a noun.

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

As verbs, mumble is a hyponym of manducate; that is, mumble is a word with a more specific, narrower meaning than manducate:

Other hyponyms of manducate include champ, chomp, champ, gum, chaw, crunch, munch, gnaw.

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

manducate (verb)	mumble (verb)
chew (food); to bite and grind with the teeth	talk indistinctly; usually in a low voice
	grind with the gums; chew without teeth and with great difficulty