Checked vowel

In phonetics and phonology, checked vowels are those that commonly stand in a stressed closed syllable; and free vowels are those that commonly stand in a stressed open syllable.

The terms checked vowel and free vowel originated in English phonetics and phonology. They are seldom used for the description of other languages even though a distinction between vowels that usually have to be followed by a consonant and other vowels is common in most Germanic languages.

The terms checked vowel and free vowel correspond closely to the terms lax vowel and tense vowel respectively, but many linguists prefer to use the terms checked and free, as there is no clearcut phonetic definition of vowel tenseness and because by most attempted definitions of tenseness /ɔː/ and /ɑː/ are considered lax even though they behave in American English as free vowels.

Checked vowels is also used to refer to a kind of very short glottalized vowels found in someZapotecan languages that contrast with laryngealized vowels. The term checked vowel is also used to refer to a short vowel followed by a glottal stop in Mixe, which has a distinction between two kinds of glottalized syllable nuclei: checked ones, with the glottal stop after a short vowel, and nuclei with rearticulated vowels, a long vowel with a glottal stop in the middle.

In English, the checked vowels are the following:

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