In Christian charismatic circles, ecstatic utterance while in a state of religious excitation; sometimes regarded as a special spiritual language (see NT Paul's 1 Corinthians 14.9) or ability to speak in different languages (see NT Acts 2.1-15).
Speaking in tongues is a form of ecstatic speech inspired by the Spirit, bursts of praise unintelligible to the ordinary interpreter. Paul recognises but does not fully encourage this phenomenon. At Pentecost Ac, describes a similar happening, when the apostles preach intelligibly in tongues unknown to themselves.
a God-given language
A "miracle" in which someone "miraculously" begins dishing out foreign-sounding words out of his mouth. The faithful cattle immediately think god made him speak and understand what he's saying. Fact is, what the speaker says is completely incomprehensible babble that makes no sense whatsoever, even if you've gotten high on a very powerful cocktail of hallucinogenics.
Speaking in unlearned languages. See "Pentecostal" .