sun letter

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun 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: الصّين. The fourteen sun letters are: