vernacular

(noun) a characteristic language of a particular group (as among thieves). Synonyms: slang, cant, jargon, lingo, argot, patois. Example: "They don't speak our lingo."

(noun) the everyday speech of the people (as distinguished from literary language).

(adj) being or characteristic of or appropriate to everyday language. Synonyms: common, vulgar. Examples: "Common parlance." "A vernacular term." "Vernacular speakers." "The vulgar tongue of the masses." "The technical and vulgar names for an animal species."