salesperson vs clerk

salesperson and clerk both are nouns.

Word	Noun	Adjective	Verb	Adverb
salesperson	Yes	No	No	No
clerk	Yes	No	Yes	No

As nouns, clerk is a hyponym of salesperson; that is, clerk is a word with a more specific, narrower meaning than salesperson:

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)
clerk: a salesperson in a store

salesperson (noun)	clerk (noun)
a person employed to represent a business and to sell its merchandise (as to customers in a store or to customers who are visited)	an employee who performs clerical work (e.g., keeps records or accounts)
	a salesperson in a store

salesperson (verb)	clerk (verb)
	work as a clerk, as in the legal business