cost vs put back

cost is a noun but put back is not a noun.

Word	Noun	Adjective	Verb	Adverb
cost	Yes	No	Yes	No
put back	No	No	Yes	No

As verbs, put back is a hyponym of cost; that is, put back is a word with a more specific, narrower meaning than cost:

Other hyponyms of cost include knock back, set back.

cost (noun)	put back (noun)
the property of having material worth (often indicated by the amount of money something would bring if sold)
value measured by what must be given or done or undergone to obtain something
the total spent for goods or services including money and time and labor

cost (verb)	put back (verb)
be priced at	put something back where it belongs
require to lose, suffer, or sacrifice	cost a certain amount