base on balls vs accomplishment

base on balls and accomplishment both are nouns.

Word	Noun	Adjective	Verb	Adverb
base on balls	Yes	No	No	No
accomplishment	Yes	No	No	No

As nouns, accomplishment is a hypernym of base on balls; that is, accomplishment is a word with a broader meaning than base on balls:

base on balls: (baseball) an advance to first base by a batter who receives four balls
accomplishment: the action of accomplishing something

Other hypernyms of base on balls include achievement.

base on balls (noun)	accomplishment (noun)
(baseball) an advance to first base by a batter who receives four balls	the action of accomplishing something
	an ability that has been acquired by training