rosin bag vs baseball equipment

rosin bag and baseball equipment both are nouns.

Word	Noun	Adjective	Verb	Adverb
rosin bag	Yes	No	No	No
baseball equipment	Yes	No	No	No

As nouns, baseball equipment is a hypernym of rosin bag; that is, baseball equipment is a word with a broader meaning than rosin bag:

rosin bag: a bag filled with rosin; used by baseball pitchers to improve their grip on the ball
baseball equipment: equipment used in playing baseball

Other hypernyms of rosin bag include bag.

rosin bag (noun)	baseball equipment (noun)
a bag filled with rosin; used by baseball pitchers to improve their grip on the ball	equipment used in playing baseball