Sun Letters and Moon Letters: Why 'Al-' Sometimes Changes Sound
How the Arabic definite article behaves differently before 14 'sun' letters and 14 'moon' letters, with examples and a simple rule.
The Arabic word for "the" is ال (al-), attached to the front of a noun. Its pronunciation quietly changes depending on the first letter of the word it joins — a rule that trips up many beginners but is actually very regular.
The rule in one line
Before a moon letter, the lam is pronounced as written: al-. Before a sun letter, the lam is silent and the following consonant is doubled: ash-, an-, ad- and so on.
Moon letters (14)
ا ب ج ح خ ع غ ف ق ك م ه و ي
Example: القمر (al-qamar, "the moon") — the lam is pronounced, and so the word is said al-qamar. The name "moon letters" comes from this very word.
Sun letters (14)
ت ث د ذ ر ز س ش ص ض ط ظ ل ن
Example: الشمس (ash-shams, "the sun") — the lam merges into the shin, and the word is pronounced ash-shams, not al-shams.
More examples
- الكتاب — al-kitab ("the book"), moon letter kaf
- المدرسة — al-madrasa ("the school"), moon letter mim
- الرجل — ar-rajul ("the man"), sun letter ra
- النور — an-nur ("the light"), sun letter nun
- الدرس — ad-dars ("the lesson"), sun letter dal
In writing, nothing changes
The spelling stays ال in both cases. Only the pronunciation shifts. When vowel marks are included, a sun-letter word will show a shadda on its first consonant, signalling the doubling.
Why the pattern exists
The sun letters are all made with the tongue near the front of the mouth, close to where the lam is articulated. Assimilating the lam into these sounds makes speech smoother — the same reason English changes "in-" to "im-" before "p" in "impossible".
How to practise
- Take ten common nouns, mark each as sun or moon, and say the definite form aloud.
- Memorise the fourteen sun letters as a list once, then treat everything else as moon.
- Listen for the doubled consonants in native speech.
- When you look up a word in a dictionary, ignore the "al-" and use the first root letter to find it.
Dictionary note
Most dictionaries list nouns without the article, so search for the word itself rather than al- plus the word.
Search Arabic nouns with or without the article in English Arabic Dictionary →
English Arabic Dictionary
Offline English–Arabic dictionary with meanings, pronunciation and script support
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