chroneme

In spoken language, a chroneme is a basic, theoretical unit of sound that can distinguish words by duration only of a vowel or consonant. The noun chroneme is derived from Greek χρονος (chronos, time), and the suffixed -eme, which is analogous to the -eme in phoneme. However, this term does not have wide currency, and may even be unknown to phonologists who work on languages claimed to have chronemes.
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