Attenuation, also known as slenderization, refers to the palatal characteristic of a consonant's secondary articulation. Slender sounds are said to be palatalized where the the tongue body is moved closer to the hard palate; these sounds contrast with broad sounds whose articulation involves the soft palate at the back of the mouth. The broad and slender distinction is marked overtly in the Gaelic writing system where slender consonants go with slender vowels (i.e. <i, e>) and broad consonants go with broad vowels (i.e. <a, o u>).
In Gaelic, attenuation is sometimes used as a morphological cue in Noun Declension and is part of a four way phonemic contrast in sonorants.
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- Lamb, William (2003) Scottish Gaelic. 2nd edition. Munich: Lingcom Europa