finisher vs relief pitcher

finisher and relief pitcher both are nouns.

Word	Noun	Adjective	Verb	Adverb
finisher	Yes	No	No	No
relief pitcher	Yes	No	No	No

As nouns, relief pitcher is a hypernym of finisher; that is, relief pitcher is a word with a broader meaning than finisher:

finisher: (baseball) a relief pitcher who can protect a lead in the last inning or two of the game
relief pitcher: a pitcher who does not start the game

Other hypernyms of finisher include fireman, reliever.

finisher (noun)	relief pitcher (noun)
an animal that wins in a contest of speed	a pitcher who does not start the game
a race car that finishes a race
a worker who performs the last step in a manufacturing process
a painter who applies a finishing coat
(baseball) a relief pitcher who can protect a lead in the last inning or two of the game
a racing driver who finishes a race