caller vs convener

caller and convener both are nouns.

Word	Noun	Adjective	Verb	Adverb
caller	Yes	Yes	No	No
convener	Yes	No	No	No

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

caller (noun)	convener (noun)
a social or business visitor	the member of a group whose duty it is to convene meetings
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)	convener (adjective)
providing coolness
fresh