caller vs caller-up

caller and caller-up both are nouns.

Word	Noun	Adjective	Verb	Adverb
caller	Yes	Yes	No	No
caller-up	Yes	No	No	No

As nouns, caller and caller-up are synonyms defined as:

Other synonyms of caller include phoner, telephoner.

caller (noun)	caller-up (noun)
a social or business visitor	the person initiating a telephone call
the person initiating a telephone call
the person who convenes a meeting
someone who proclaims or summons in a loud voice
a person who announces the changes of steps during a dance
the bettor in a card game who matches the bet and calls for a show of hands
an investor who buys a call option

caller (adjective)	caller-up (adjective)
providing coolness
fresh