obtain vs shop

obtain is not a noun while shop is a noun.

Word	Noun	Adjective	Verb	Adverb
obtain	No	No	Yes	No
shop	Yes	No	Yes	No

As verbs, shop is a hyponym of obtain; that is, shop is a word with a more specific, narrower meaning than obtain:

obtain (noun)	shop (noun)
	a course of instruction in a trade (as carpentry or electricity)
	a mercantile establishment for the retail sale of goods or services
	small workplace where handcrafts or manufacturing are done

obtain (verb)	shop (verb)
receive a specified treatment (abstract)	give away information about somebody
come into possession of	do one's shopping
be valid, applicable, or true	shop around; not necessarily buying
	do one's shopping at; do business with; be a customer or client of