cash in vs cash

cash in is not a noun while cash is a noun.

Word	Noun	Adjective	Verb	Adverb
cash in	No	No	Yes	No
cash	Yes	No	Yes	No

As verbs, cash in and cash are synonyms defined as:

cash in (noun)	cash (noun)
	money in the form of bills or coins
	prompt payment for goods or services in currency or by check

cash in (verb)	cash (verb)
exchange for cash	exchange for cash