SLANG
Slang is a part of the vocabulary consisting of commonly understood and widely used words and expressions of humorous or derogatory characterintentional substitutes for neutral or elevated words and expressions. (U. M. Skrebnev) Slang is everything which is out of the books. (M. Goldenkov) Slang is the special vocabulary used by any set of persons of a low or disreputable character; language of a low and vulgar type (The Oxford English dictionary)
to expresses a certain emotional attitude; allows speakers the freedom to play with and enjoy the language; to make words up; to adopt new expressions indiscriminately; to use language for humor, irony, sarcasm, and irreverence; to name things indirectly and figuratively, especially through metaphor, metonymy, and irony.
to make an impression; to be on a colloquial level; to lend an air of solidity; to be novel; to be different; not to be understood by somebody; to demonstrate the class that one belongs to; to be an interesting speaker; to enrich the language; to induce friendliness.
1. Various figures of speech participate in slang formation: killing-astonishing (hyperbole) clear as mud (irony) 2. The addition of a particle like OUT, OFF or ON to a noun, adjective or verb, to form a phrasal verb. blimp out (to eat too much) blow off (to ignore) 3. To use Abbreviations: Sup? -What’s up? Pro -professional