Sun & Moon Letters

Sun letters "الحُروف الشَّمسِيه" (al-Huruuf ash-shamsiya) and Moon letters "الحُروف القَمَرِيه" (al-Huruuf al-qamariya) are two groups that make up the consonants in Arabic. Sun-letters drop the “ل” (l) sound of the definite article (ال) and replace it with a double consonant sound “shadda” (see special vowels). Moon letters have no effect on the definite article.

The 14 Sun-letters are: 

(ﻥ ,ﻝ ,ﻅ ,ﻁ ,ﺽ ,ﺹ ,ﺵ ,ﺱ ,ﺯ ,ﺭ ,ﺫ ,ﺩ ,ﺙ ,ﺕ) 

(t, th, d, th, r, z, s, sh, S, D, T, Z, l, n)

On this site all transliterated words with the definite article are written as follows:

Sun-letter: الرّاجِل - al + raajil = ar-raajil (the man)

Moon-letter: الوَلَد - al + walad = al-walad (the boy)