Slang
'Slang' refers to a deviation in language use, be it vocabulary or expressions, from the standardized form of a particular language. Technically speaking from a linguistic point of view, the word is not recognized. From a social point of view, we often view slang as a 'lesser' variety of language use, often associated with dialects or accents. Slang often defines who the members are of an 'in-crowd'. It is a social marker.