vernacular vs argot

vernacular and argot both are nouns.

Word	Noun	Adjective	Verb	Adverb
vernacular	Yes	Yes	No	No
argot	Yes	No	No	No

As nouns, vernacular and argot are synonyms defined as:

vernacular and argot: a characteristic language of a particular group (as among thieves)

Other synonyms of vernacular include cant, jargon, lingo, patois, slang.

vernacular (noun)	argot (noun)
the everyday speech of the people (as distinguished from literary language)	a characteristic language of a particular group (as among thieves)
a characteristic language of a particular group (as among thieves)

vernacular (adjective)	argot (adjective)
being or characteristic of or appropriate to everyday language