Tenseness

Pronunciation of a sound with greater muscular effort than normal

In phonology, tenseness or tensing is, most broadly, the pronunciation of a sound with greater muscular effort or constriction than is typical. More specifically, tenseness is the pronunciation of a vowel with less centralization, longer duration, and narrower mouth width compared with another vowel. The opposite quality to tenseness is known as laxness or laxing: the pronunciation of a vowel with relatively more centralization, shorter duration, and more widening.

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