receipt vs acknowledge

receipt is a noun but acknowledge is not a noun.

Word	Noun	Adjective	Verb	Adverb
receipt	Yes	No	Yes	No
acknowledge	No	No	Yes	No

As verbs, receipt and acknowledge are synonyms defined as:

receipt (noun)	acknowledge (noun)
the act of receiving
an acknowledgment (usually tangible) that payment has been made

receipt (verb)	acknowledge (verb)
mark or stamp as paid	accept as legally binding and valid
report the receipt of	accept (someone) to be what is claimed or accept his power and authority
	declare to be true or admit the existence or reality or truth of
	express obligation, thanks, or gratitude for
	report the receipt of
	express recognition of the presence or existence of, or acquaintance with