telephonist vs operator

telephonist and operator both are nouns.

Word	Noun	Adjective	Verb	Adverb
telephonist	Yes	No	No	No
operator	Yes	No	No	No

As nouns, operator is a hypernym of telephonist; that is, operator is a word with a broader meaning than telephonist:

Other hypernyms of telephonist include manipulator.

telephonist (noun)	operator (noun)
someone who helps callers get the person they are calling	an agent that operates some apparatus or machine
	someone who owns or operates a business
	a shrewd or unscrupulous person who knows how to circumvent difficulties
	a speculator who trades aggressively on stock or commodity markets
	(mathematics) a symbol or function representing a mathematical operation