segment (linguistics)

In linguistics (and phonetics), segment is used primarily “to refer to any  discrete unit that can be identified, either physically or auditorily, in the stream of speech” (after A Dictionary of Linguistics & Phonetics, David Crystal, 2003, pp. 408–409).In spoken languages, a segment may be a consonant, vowel, tone, or stress. It is not clear whether sign languages have equivalent segments. In phonetics, the smallest perceptible segment is a phone.
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