batsman vs slugger

batsman and slugger both are nouns.

Word	Noun	Adjective	Verb	Adverb
batsman	Yes	No	No	No
slugger	Yes	No	No	No

As nouns, batsman and slugger are synonyms defined as:

Other synonyms of batsman include batter, hitter.

batsman (noun)	slugger (noun)
(baseball) a ballplayer who is batting	(baseball) a ballplayer who is batting
	a boxer noted for an ability to deliver hard punches