salesman vs sales rep

salesman and sales rep both are nouns.

Word	Noun	Adjective	Verb	Adverb
salesman	Yes	No	No	No
sales rep	Yes	No	No	No

As nouns, sales rep is a hypernym of salesman; that is, sales rep is a word with a broader meaning than salesman:

salesman: a man salesperson
sales rep: a person employed to represent a business and to sell its merchandise (as to customers in a store or to customers who are visited)

Other hypernyms of salesman include adult male, man, sales representative, salesperson.

salesman (noun)	sales rep (noun)
a man salesperson	a person employed to represent a business and to sell its merchandise (as to customers in a store or to customers who are visited)