retail store vs shop

retail store and shop both are nouns.

Word	Noun	Adjective	Verb	Adverb
retail store	Yes	No	No	No
shop	Yes	No	Yes	No

As nouns, shop is a hyponym of retail store; that is, shop is a word with a more specific, narrower meaning than retail store:

retail store (noun)	shop (noun)
a place of business for retailing goods	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

retail store (verb)	shop (verb)
	give away information about somebody
	do one's shopping
	shop around; not necessarily buying
	do one's shopping at; do business with; be a customer or client of