sales demonstrator vs demonstrator

sales demonstrator and demonstrator both are nouns.

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

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

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

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