gibber vs nonsense

gibber and nonsense both are nouns.

Word	Noun	Adjective	Verb	Adverb
gibber	Yes	No	Yes	No
nonsense	Yes	Yes	No	No

As nouns, nonsense is a hypernym of gibber; that is, nonsense is a word with a broader meaning than gibber:

Other hypernyms of gibber include bunk, hokum, meaninglessness, nonsensicality.

gibber (noun)	nonsense (noun)
unintelligible talking	ornamental objects of no great value
	a message that seems to convey no meaning

gibber (adjective)	nonsense (adjective)
	having no intelligible meaning

gibber (verb)	nonsense (verb)
speak (about unimportant matters) rapidly and incessantly
chatter inarticulately; of monkeys