Affection (linguistics)

In Celtic linguistics, affection (also known as vowel affection, infection or vowel mutation) is the change in the quality of a vowel under the influence of the vowel of the following, final syllable. It is a type of anticipatory (or regressive) assimilation at a distance. Subsequently, the vowel triggering the change was normally lost. Some grammatical suffixes cause i-affection; Welsh: gair word + -iadur device suffix yields geiriadur dictionary, the -ai- in gair becomes -ei-.

The two main types of affection are a-affection and i-affection. There is also u-affection, which is more usually referred to as u-infection. i-affection is an example of i-mutation, and may be compared to Germanic umlaut. More rarely, the term "affection" (like "umlaut") may be heard applied to other languages, and is then a synonym for i-mutation generally.

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