dirty word vs backside

dirty word and backside both are nouns.

Word	Noun	Adjective	Verb	Adverb
dirty word	Yes	No	No	No
backside	Yes	No	No	No

dirty word (noun)	backside (noun)
an offensive or indecent word or phrase	the fleshy part of the human body that you sit on
a word that is considered to be unmentionable	the side of an object that is opposite its front