weight gainer vs worker

weight gainer and worker both are nouns.

Word	Noun	Adjective	Verb	Adverb
weight gainer	Yes	No	No	No
worker	Yes	No	No	No

As nouns, worker is a hypernym of weight gainer; that is, worker is a word with a broader meaning than weight gainer:

Other hypernyms of weight gainer include actor, doer.

weight gainer (noun)	worker (noun)
a person who gains weight	sterile member of a colony of social insects that forages for food and cares for the larvae
	a person who works at a specific occupation
	a member of the working class (not necessarily employed)
	a person who acts and gets things done