Nūn Sākina and Tanwīn II: Idghām · Tajweed

What idghām is

Idghām (إِدْغَامٌ) means "merging". When nūn sākina or tanwīn is followed by one of the six letters collected in the word يَرْمَلُونَ (ي ر م ل و ن), the nūn is not pronounced as a separate letter. Instead the tongue goes straight to the next letter, which is pronounced doubled, as if it carried a shadda. The six letters split into two groups: with four of them a nasal hum (ghunna) remains during the merge; with two it does not. Idghām of nūn sākina happens only across two words; inside a single word it does not apply.

Rule 1: Idghām with ghunna (ي ن م و)

Before ي ن م و (remembered as يَنْمُو) the nūn merges into the following letter while the nasal sound continues for two counts. With ن and م the merge is complete: you simply hear a doubled nūn or mīm with ghunna. With ي and و the merge is incomplete: the letter itself is ي or و, but the nūn's ghunna hums through it, as in مَن يَعْمَلْ = may-yaʿmal with a nasal yy.

مِّن مَّسَدٍ
mim-masad
of palm fibre
نْ merges into م with ghunna (111:5).
فَمَن يَعْمَلْ
famay-yaʿmal
so whoever does
نْ merges into ي; the ghunna hums through the doubled yāʾ (99:7).
قُرْآنٌ مَّجِيدٌ
qurʾānum-majīd
a glorious Qurʾān
tanwīn merges into م with ghunna (85:21).
خَيْرٌ وَأَبْقَىٰ
khayruw-wa abqā
better and more lasting
tanwīn merges into و with ghunna (87:17).
يَوْمَئِذٍ نَّاعِمَةٌ
yawmaʾidhin-nāʿima
that Day, joyful
tanwīn merges into ن; a doubled nūn with ghunna (88:8).
صِرَاطٍ مُّسْتَقِيمٍ
ṣirāṭim-mustaqīm
a straight path
tanwīn merges into م with ghunna (36:4).

Rule 2: Idghām without ghunna (ل ر)

Before ل and ر the nūn merges completely and no nasal sound remains at all. You pronounce the next letter doubled and move on: مِّن رَّبِّهِمْ is mir-rabbihim, هُدًى لِّلْمُتَّقِينَ is hudal-lil-muttaqīn. Any trace of ghunna here is an error; the nūn has fully become the following letter.

مِّن رَّبِّهِمْ
mir-rabbihim
from their Lord
نْ merges into ر; no ghunna (2:5).
هُدًى لِّلْمُتَّقِينَ
hudal-lil-muttaqīn
guidance for the God-fearing
tanwīn merges into ل; no ghunna (2:2).
وَيْلٌ لِّكُلِّ هُمَزَةٍ لُّمَزَةٍ
waylul-likulli humazatil-lumaza
woe to every slanderer and backbiter
two tanwīns merge into ل (104:1).
وَلَمْ يَكُن لَّهُ
wa lam yakul-lahu
and there is not for Him
نْ merges into ل (112:4).
عِيشَةٍ رَّاضِيَةٍ
ʿīshatir-rāḍiya
a pleasant life
tanwīn merges into ر (101:7).

The six letters of idghām

Letter	Ghunna?	Merge	Example
ي	yes, two counts	incomplete: the yāʾ is heard with nasal hum	مَن يَعْمَلْ
ن	yes, two counts	complete: a doubled nūn	يَوْمَئِذٍ نَّاعِمَةٌ
م	yes, two counts	complete: a doubled mīm	مِّن مَّسَدٍ
و	yes, two counts	incomplete: the wāw is heard with nasal hum	خَيْرٌ وَأَبْقَىٰ
ل	no	complete: a doubled lām	هُدًى لِّلْمُتَّقِينَ
ر	no	complete: a doubled rāʾ	مِّن رَّبِّهِمْ

Reading the script

The muṣḥaf marks idghām by leaving the nūn without a sukūn sign and writing a shadda on the next letter: مِن مَّسَدٍ. With tanwīn, the two signs are written one after the other instead of stacked (ـٍ becomes a "following" tanwīn). In the Fusha Path reader, idghām with ghunna is shaded purple and idghām without ghunna is shaded brown; the ghunna itself, wherever it occurs, is marked grey.