Nūn Sākinah and Tanwīn
Iẓhār, idghām, iqlāb, ikhfāʾ: what happens to the nūn depending on the letter after it
Core idea
A nūn with sukūn, or a tanwīn, follows one of four rules, set by the letter that comes next: pronounced clearly before the throat letters, merged into y r m l w n, turned into a mīm before bāʾ, and hidden before the other fifteen letters.
Why it matters
These rules come up constantly — hardly an ayah is without a nūn sākinah or a tanwīn. They are also most of the green in the mushaf: know the letter after the nūn and you know both the rule and its colour.
Lesson
Nūn sākinah is a nūn with no vowel, written and pronounced both when joining and when pausing; it appears in nouns, verbs and particles, mid-word or at the end: anʿamta, min.
Tanwīn is an extra nūn with sukūn added at the end of a noun — heard but not written as a letter, and dropped when you pause. It is written as a double fatḥa, ḍamma or kasra: nāran, nārun, ʿīshatin. When you join, it follows exactly the rules of nūn sākinah.
The rule is set by the next letter, whether in the same word or at the start of the next: - Iẓhār (clear) before the six throat letters ʾ h ʿ ḥ gh kh. The nūn is pronounced clearly, with no extra nasal hold, because the throat is far from its makhraj. - Idghām (merging) into the six letters of yarmalūn: with ghunnah into y n m w (yanmū), without ghunnah into l and r. It only happens across two words. - Iqlāb (turning) before bāʾ only: the nūn becomes a hidden mīm with ghunnah. The mushaf writes a small mīm over the nūn, or in place of the tanwīn's second mark. - Ikhfāʾ (hiding) before the other fifteen letters: between clear and merged — the ghunnah stays and the nūn itself is hidden.
The ghunnah in idghām with ghunnah, iqlāb and ikhfāʾ lasts two counts. Ḥafṣ and Qālūn agree on all four rules. What differs in the printed Qālūn mushaf is the marks, not the sound: it writes a sukūn on the merged nūn and a shadda on the next letter — fa-man yyaʿmal.
In detail, with examples
1. Iẓhār — pronounced clearly
Before the six throat letters. No colour in the mushaf: the nūn is read as written.
ء هـ ع ح غ خThe iẓhār letters
The nūn comes from its own makhraj with no extra nasal hold. Remember the letters by the first letters of akhī hāka ʿilman ḥāzahu ghayru khāsir.
2. Idghām — merging
Into y r m l w n — and only across two words.
ي ن م وIdghām with ghunnah
The nūn disappears into the next letter, which becomes doubled, with a two-count ghunnah. Letters: yanmū. Green in the mushaf.
Al-Zalzalah 99:7فَمَن يَعْمَلْ
Nūn sākinah into yāʾ: the nūn goes, its ghunnah stays on the doubled yāʾ.
3. Iqlāb — turning into mīm
Before bāʾ only. The mushaf marks it with a small mīm.
4. Ikhfāʾ — hiding
Before the remaining fifteen letters. Green in the mushaf.
ص ذ ث ك ج ش ق س د ط ز ف ت ض ظThe ikhfāʾ letters
The nūn is said between clear and merged, with no shadda, and a two-count ghunnah. The tongue already moves towards the next letter's makhraj, so the ghunnah is heavy before raised letters and light before the others. The letters are the first letters of the verse ṣif dhā thanā kam jāda shakhṣun qad samā / dum ṭayyiban zid fī tuqan ḍaʿ ẓālimā.
In your mushaf
Idghām with ghunnah, iqlāb and ikhfāʾ are all green in the app's mushaf, because they share the ghunnah that comes from the khayshūm (lesson 1). Idghām without ghunnah makes the nūn grey, because it is not pronounced. Iẓhār has no colour. Change these colours in Settings and the examples here change too.
Key points
- 1
Tanwīn is an extra nūn sākinah, heard not written — same rules.
- 2
Iẓhār before the six throat letters: ʾ h ʿ ḥ gh kh.
- 3
Idghām into yarmalūn: with ghunnah into yanmū, without into l and r — only across two words.
- 4
Iqlāb before bāʾ: a hidden mīm with ghunnah, marked by a small mīm.
- 5
Ikhfāʾ before the other fifteen, with a two-count ghunnah.
- 6
Ḥafṣ and Qālūn agree on all four rules; only the written marks differ.
Glossary
النُّون السَّاكِنَة
al-nūn al-sākinah
a nūn with no vowel, written and pronounced
التَّنْوِين
al-tanwīn
an extra nūn sākinah at the end of a noun, heard not written
الإظْهار
al-iẓhār
saying the letter clearly from its makhraj
الإدْغام
al-idghām
merging a still letter into a voweled one so they become one doubled letter
الإقْلاب
al-iqlāb
turning the nūn into a hidden mīm before bāʾ
الإخْفاء
al-ikhfāʾ
saying the nūn between clear and merged, with ghunnah
Test yourself
Question 1 of 8
How many rules do nūn sākinah and tanwīn have?
Sources
لِلنُّونِ إِنْ تَسْكُنْ وَلِلتَّنْوِينِ ... أَرْبَعُ أَحْكَامٍ فَخُذْ تَبْيِينِي
“The nūn, when still, and the tanwīn have four rules — so take my explanation.”
Sulaymān al-Jamzūrī (fl. 1198 AH), Tuḥfat al-Aṭfāl
وَحُكْمُ تَنْوِينٍ وَنُونٍ يُلْفَى ... إِظْهَارٌ ادْغَامٌ وَقَلْبٌ إِخْفَا
“The rule of tanwīn and nūn is found to be: iẓhār, idghām, iqlāb, ikhfāʾ.”
Ibn al-Jazarī (d. 833 AH), al-Muqaddima al-Jazariyya
Prepared from
This lesson was written in our own words from the material below; no text or image from it is reproduced.
- «شجرة أحكام النون الساكنة والتنوين» — one-page tree: the four branches and each rule's letters; rebuilt in our own layout
- «صور أحكام النون الساكنة والتنوين» — illustrated pages of a printed book: definitions and the mushaf marks; rewritten, no image reused
- «تشجيرات أحكام التجويد» — booklet of tree diagrams: cross-check of the rules' order