designated hitter vs hitter

designated hitter and hitter both are nouns.

Word	Noun	Adjective	Verb	Adverb
designated hitter	Yes	No	No	No
hitter	Yes	No	No	No

As nouns, hitter is a hypernym of designated hitter; that is, hitter is a word with a broader meaning than designated hitter:

designated hitter: a ballplayer who is designated to bat in place of the pitcher
hitter: (baseball) a ballplayer who is batting

Other hypernyms of designated hitter include batsman, batter, slugger.

designated hitter (noun)	hitter (noun)
a ballplayer who is designated to bat in place of the pitcher	(baseball) a ballplayer who is batting
	someone who hits