antibiotic vs antibacterial

antibiotic and antibacterial both are nouns.

Word	Noun	Adjective	Verb	Adverb
antibiotic	Yes	Yes	No	No
antibacterial	Yes	Yes	No	No

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

antibiotic: a chemical substance derivable from a mold or bacterium that can kill microorganisms and cure bacterial infections
antibacterial: any drug that destroys bacteria or inhibits their growth

Other hypernyms of antibiotic include antibacterial drug, bactericide.

antibiotic (noun)	antibacterial (noun)
a chemical substance derivable from a mold or bacterium that can kill microorganisms and cure bacterial infections	any drug that destroys bacteria or inhibits their growth

antibiotic (adjective)	antibacterial (adjective)
of or relating to antibiotic drugs	destroying bacteria or inhibiting their growth