callback vs asking

callback and asking both are nouns.

Word	Noun	Adjective	Verb	Adverb
callback	Yes	No	No	No
asking	Yes	No	No	No

As nouns, asking is a hypernym of callback; that is, asking is a word with a broader meaning than callback:

callback: a request by the manufacturer of a defective product to return the product (as for replacement or repair)
asking: the verbal act of requesting

Other hypernyms of callback include request.

callback (noun)	asking (noun)
a request by the manufacturer of a defective product to return the product (as for replacement or repair)	the verbal act of requesting