Informal language

Slang refers to words, phrases and uses that are regarded as very informal and often restricted to special context or peculiar to a specified profession class and the like. Slang words are used in specific social groups, like teenagers.

In its earliest attested use (1756), the word slang referred to the vocabulary of "low or disreputable" people. By the early nineteenth century, it was no longer exclusively associated with disreputable people, but continued to be applied to language use below the level of standard educated speech. The origin of the word is uncertain, although it appears to be connected with thieves' cant. A Scandinavian origin has been proposed (compare, for example, Norwegian slengenavn, which means "nickname"), but is discounted by the Oxford English Dictionary based on "date and early associations". Jonathan Green however agrees with the possibility of a Scandinavian origin, suggesting the same root as that of sling, which means "to throw", and noting that slang is a thrown language - a quick, honest way to make your point.

Few linguists have endeavored to clearly define what constitutes slang. However, what is known is that slang is a linguistic phenomenon ever present and consistently changing among every subculture worldwide. Some suggest that the reason slang exists is because we must come up with new ways of defining new experiences that have surfaced with time and modernity. Attempting to remedy the lack of a clear definition, however, Bethany K. Dumas and Jonathan Lighter argue that an expression should be considered "true slang" if it meets at least two of the following criteria:

Michael Adams remarks that, "[Slang] is liminal language... it is often impossible to tell, even in context, which interests and motives it serves... slang is on the edge." Slang dictionaries, collecting thousands of slang entries, offer a broad, empirical window into the motivating forces behind slang".

While many forms of language may be considered "sub-standard", slang remains distinct from colloquial and jargon terms because of its specific social contexts. While considered inappropriate in formal writing, colloquial terms are typically considered acceptable in speech across a wide range of contexts, while slang tends to be considered unacceptable in many contexts. Jargon refers to language used by personnel in a particular field, or language used to represent specific terms within a field to those with a particular interest. Although jargon and slang can both be used to exclude non–group members from the conversation, the intention of jargon is to optimize conversation using terms that imply technical understanding. On the other hand, slang tends to emphasize social and contextual understanding.

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