vulgarism vs dirty word

vulgarism and dirty word both are nouns.

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

As nouns, vulgarism and dirty word are synonyms defined as:

Other synonyms of vulgarism include filth, obscenity, smut.

vulgarism (noun)	dirty word (noun)
the quality of lacking taste and refinement	an offensive or indecent word or phrase
an offensive or indecent word or phrase	a word that is considered to be unmentionable