conlang

n. constructed language, artificial language, language created intentionally for a particular use or purpose, language invented specifically by a particular person or small group

A constructed or artificial language — known colloquially/informally as a conlang — is a language whose phonology, grammar, and/or vocabulary have been devised by an individual or group, instead of having naturally evolved as part of a culture. There are many possible reasons to create a constructed language: to ease human communication (see international auxiliary language and code); to bring fiction or an associated constructed world to life; linguistic experimentation; celebration of one's aesthetic tastes in language; and language games.
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