Syllable weight

In linguistics, syllable weight is the concept that syllables pattern together according to the number and/or duration of segments in the rime. In classical poetry, both Greek and Latin, distinctions of syllable weight were fundamental to the meter of the line.

A heavy syllable is a syllable with a branching nucleus or a branching rime, although not all such syllables are heavy in every language. A branching nucleus generally means the syllable has a long vowel or a diphthong; this type of syllable is abbreviated CVV. A syllable with a branching rime is a closed syllable, that is, one with a coda (one or more consonants at the end of the syllable); this type of syllable is abbreviated CVC. In some languages, both CVV and CVC syllables are heavy, while a syllable with a short vowel as the nucleus and no coda (a CV syllable) is a light syllable. In other languages, only CVV syllables are heavy, while CVC and CV syllables are light. In yet other languages, CVV syllables are heavy and CV syllables are light, while some CVC syllables are heavy (for instance if the coda is a sonorant) and other CVC syllables are light (for instance if the coda is an obstruent). Some languages distinguish a third type, CVVC syllables (with both a branching nucleus and a coda) and/or CVCC syllables (with a coda consisting of two or more consonants) as superheavy syllables.

In moraic theory, heavy syllables are analyzed as containing two morae, light syllables one, and superheavy syllables three.

The distinction between heavy and light syllables plays an important role in the phonology of some languages, especially with regard to the assignment of stress. For instance, in the Sezer stress pattern in Turkish observed in place names, the main stress occurs as an iamb (i.e. penultimate stress) one syllable to the left of the final syllable: (L'L)σ. However, when the foot contains a heavy syllable in the first syllable while the second syllable is light, the iamb shifts to a trochee (i.e. antepenultimate stress) because there is a requirement that main stress fall on a heavy syllable whenever possible: ('HL)σ, and not *(H'L)σ.

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