A living language such as English is a dynamic flow of spoken and written terms, eternally evolving. Whenever people use the language they cause it to flow in and around itself, creating new meanings, ways to express. Term “slang” reflects the dynamics of the language and therefore is very obscure and ambiguous. Although it is spread so much that now can easily be found practically in all kinds of contemporary literary works, yet there is no easy mechanism for identifying it. The absolute truth about slang was revealed by Lighter and Dumas that anyone can recognize slang, but no one can define it. There is hardly any other term that is as ambiguous and obscure as the term slang.
Slang is a controversial topic nowadays, and the debate on its definitions, classification and linguistic relevance is still heated. Most linguists and lexicographers admit that the origin of the word slang is “uncertain” or “unknown”. One notable exception is Skeat, a lexicographer, who claims that slang (“vulgar language”) is of Scandinavian origin and a derivation of Icelandic slyngva (“to sling”), which can be compared with the Norwegian verb slengja (“to sling the jaw”) and the Norwegian noun slengjeord (“slang word”), used for insulting words.
In a similar vein, Partridge referred by Eble in her book “Slang and Sociability; in-group language among college students” says that certain resemblances between English word slang and the Scandinavian sling suggest that the words have developed from a common Germanic root. In contrast, one of the Swedish researchers on slang Anna-Brita Stenstrom, in her article “From slang to slanguage: a description based on teenage talk” shows that one of the Swedish dictionaries consulted “Bonniers Stora Lexicon” maintains that the Swedish word slang comes from English slang, and that the origin is unknown.
Also she provides an identical opinion of Swedish encyclopedia “Nationalencyclopedin”, which states that the word slang was not introduced in the Nordic countries until the middle of the 19th century. The first occurrence of the word slang is dated 1756 in the OED, according to which ultimate source is “not apparent”. Consequently, word “slang” appeared in English language earlier than in the languages of Scandinavian countries.