sulfa drug vs antibacterial

sulfa drug and antibacterial both are nouns.

Word	Noun	Adjective	Verb	Adverb
sulfa drug	Yes	No	No	No
antibacterial	Yes	Yes	No	No

As nouns, antibacterial is a hypernym of sulfa drug; that is, antibacterial is a word with a broader meaning than sulfa drug:

sulfa drug: antibacterial consisting of any of several synthetic organic compounds capable of inhibiting the growth of bacteria that require PABA
antibacterial: any drug that destroys bacteria or inhibits their growth

Other hypernyms of sulfa drug include antibacterial drug, bactericide.

sulfa drug (noun)	antibacterial (noun)
antibacterial consisting of any of several synthetic organic compounds capable of inhibiting the growth of bacteria that require PABA	any drug that destroys bacteria or inhibits their growth

sulfa drug (adjective)	antibacterial (adjective)
	destroying bacteria or inhibiting their growth