trainer vs manager

trainer and manager both are nouns.

Word	Noun	Adjective	Verb	Adverb
trainer	Yes	No	No	No
manager	Yes	No	No	No

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

Other hyponyms of trainer include coach, handler, animal trainer, handler.

trainer (noun)	manager (noun)
simulator consisting of a machine on the ground that simulates the conditions of flying a plane	someone who controls resources and expenditures
one who trains other persons or animals	(sports) someone in charge of training an athlete or a team