demonstrator vs sales demonstrator

demonstrator and sales demonstrator both are nouns.

Word	Noun	Adjective	Verb	Adverb
demonstrator	Yes	No	No	No
sales demonstrator	Yes	No	No	No

As nouns, demonstrator and sales demonstrator are synonyms defined as:

demonstrator and sales demonstrator: someone who demonstrates an article to a prospective buyer

demonstrator (noun)	sales demonstrator (noun)
someone who participates in a public display of group feeling	someone who demonstrates an article to a prospective buyer
someone who demonstrates an article to a prospective buyer
a teacher or teacher's assistant who demonstrates the principles that are being taught