Idgham Rule in Tajweed Explained: With and Without Ghunnah

Idgham applies to Noon Saakinah and Tanween. Noon Saakinah is a noon letter carrying a sukoon (no vowel), and it can appear in the middle or at the end of a word. Tanween is the doubled vowel at the end of a word — the -an, -in, and -un sounds — which is really a hidden noon sound. Whenever either of these is followed by one of the six Idgham letters, the noon sound merges into that letter.

Merging means the noon is not pronounced as a separate, clear sound. Instead, the reciter moves smoothly from the previous sound into the Idgham letter, which is pronounced with a slight doubling (shaddah). That smoothness is the whole point of the rule: the Quran flows, and the joins between words disappear.

The six Idgham letters are remembered by the word Yarmaloon: Ya, Ra, Meem, Lam, Waw, and Noon. If the letter after a Noon Saakinah or Tanween is one of these six, Idgham applies. If it is any other letter, a different rule applies — Izhar (clear pronunciation), Ikhfa (hiding), or Iqlab (changing to meem) — so learning these six letters is the key to the whole rule.

The six letters split into two groups of very different sound, which is where most learners need to pay attention. Four letters take Idgham with Ghunnah (a nasal sound held for about two counts), and two letters take Idgham without Ghunnah (a clean merge with no nasal sound at all). Confusing the two groups is the most common Idgham mistake.

Idgham with Ghunnah applies when the following letter is Ya, Noon, Meem, or Waw. The noon sound merges into the letter, and a nasal Ghunnah sound — the hum that comes through the nose — is held for about two counts while the merge happens. The Ghunnah is what gives this kind of Idgham its warm, humming quality.

Listen for it in familiar verses. In the phrase man ya'mal (whoever does), the noon of man merges into the ya, with a nasal hum: may-ya'mal. In khayran yarah (good, he will see it), the tanween on khayran merges into the ya: khayray-yarah. In min ni'mah (from a blessing), the noon merges into the second noon: min-ni'mah. Once you hear the hum, you will start noticing it everywhere in recitation.

Idgham without Ghunnah applies when the following letter is Lam or Ra. Here the noon sound merges completely into the letter, with no nasal hum at all — a clean, crisp merge. This is the sharper of the two kinds of Idgham, and it is easy to hear once you know what to listen for.

A famous example is min ladunhu (from His presence), where the noon of min merges into the lam with no nasal sound: mil-ladunhu. Another is min Rabb (from a Lord), where the noon merges into the ra: mir-Rabb. A well-known tanween example is Ghafoorur Raheem (Forgiving, Merciful), where the tanween on Ghafoor merges into the ra: Ghafoorur-Raheem. If you hear a nasal hum before a lam or ra, that is the mistake to correct.

There is one famous exception, and it only concerns Noon Saakinah followed by Ya or Waw inside a single word. In four words of the Quran — ad-dunya (the world), bunyan (a building), sinwan (two shoots from one root), and qinwan (clusters) — the noon is pronounced clearly, not merged, even though Ya or Waw follows. This is called Izhar Mutlaq, and it exists so the word stays recognizable and its meaning stays clear.

The exception is easy to remember because it only happens in these four words, and a teacher will point them out as you meet them. Everywhere else, the rule holds: Noon Saakinah or Tanween followed by a Yarmaloon letter merges, with Ghunnah for Ya, Noon, Meem, and Waw, and without Ghunnah for Lam and Ra. If you are learning Tajweed, ask your tutor to listen to your Idgham specifically — it is one of the first rules a teacher checks, because it is so audible.