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sun letter

n. (cx linguistics Arabic) One of fourteen Arabic letters that cause the "L" of a preceding definite article to be assimilated in pronunciation. The sun letter suppresses the sound of the "L" and then geminates: al + ṣīn = aṣ-ṣīn. The effect of the sun letter is limited to pronunciation and does not affect the spelling, except that a shadda may be written over the sun letter and in the fully vocalised spelling lām lacks any diacritics: (m ar الصِّين). The fourteen sun letters are: