Fortition

Consonantal change

In articulatory phonetics, fortition, also known as strengthening, is a consonantal change that increases the degree of stricture. It is the opposite of the more common lenition. For example, a fricative or an approximant may become a stop. Although not as typical of sound change as lenition, fortition may occur in prominent positions, such as at the beginning of a word or stressed syllable; as an effect of reducing markedness; or due to morphological leveling.

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