Cryptophasia

Cryptophasia is a peculiar phenomenon of a language developed by twins (identical or fraternal) that only the two children could understand. The word has its roots from crypto meaning secret and phasia meaning speech disorder. Most linguists associate cryptophasia with idioglossia, which is literally the same, but cryptophasia also includes mirror
Found on http://en.wikipedia.org/wiki/Cryptophasia

cryptophasia

cryptophasia Neologisms that simulate coherent speech despite the fact that they are expressed as unintelligible conglomerations of sounds or written as a series of unintelligible letters.
Found on http://www.wordinfo.info/words/index/info/view_unit/1632/2
No exact match found