Cryptophasia

Phenomenon of a language developed by twins

Cryptophasia is the phenomenon of a language developed by twins that only the two children can understand. The word has its roots from the Greek crypto-, meaning secret, and -phasia, meaning speech. Most linguists associate cryptophasia with idioglossia, which is any language used by only one, or very few, people. Cryptophasia differs from idioglossia on including mirrored actions like twin-walk and identical mannerisms.

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