Sonority
Sonority is the quality of having a deep, pleasant sound, or the degree to which something has this sound. It is a nonbinary phonological feature categorizing sounds into a relative scale. Sonority has to do with how much acoustic energy a given speech sound has. Linguists divide speech sounds into three broad categories, vowels, consonants, and glides, according to their sonority. Sonority is a central notion in phonetics and phonology and it is essential for generalizations related to syllabic organization. The phonetic basis of sonority is contentious; it is roughly but imperfectly correlated with loudness. A primary function of sonority is to linearize segments within syllables: more sonorous sounds tend to occur more closely to the peak.
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