Idgham Mutajanisain and Mutaqaribain: Merging Letters That Sound Alike

By the time students reach this rule they usually know the noon sakin and meem sakin rules well, and they think the merging part of Tajweed is done. Then the teacher stops them at قَدْ تَبَيَّنَ and says, “Not qad-tabayyana. Qat-tabayyana.” A daal that turns into a taa? It sounds odd until you understand why.

This is the world of idgham mutajanisain and idgham mutaqaribain: merging two letters that are not the same, but are close enough in the mouth that saying both clearly would be awkward. The list of cases in the Hafs recitation is short, and once you know them you will spot them every time.

First, the three kinds of meeting letters

Whenever a letter with sukoon is followed by a letter with a vowel, Tajweed asks how close the two letters are. There are three possibilities:

Name	Meaning	Example
Mutamathilain	The same letter twice	اضْرِب بِّعَصَاكَ (idrib bi’asaaka)
Mutajanisain	Same point of articulation (makhraj), different qualities	قَد تَّبَيَّنَ (qat-tabayyana)
Mutaqaribain	Points of articulation or qualities that are close	قُل رَّبِّ (qur-rabbi)

In all three, when the first letter is sakin and the second has a vowel, the first usually merges into the second. In the mushaf you see this as a first letter with no jazm and a second letter with a shaddah, the same visual signal you learned with the sun letters. The noon sakin and meem sakin rules are really special cases of this same idea; they are covered in noon sakin and tanween rules and meem sakin rules.

Idgham mutajanisain: same place, different letters

These pairs come from the same spot in the mouth. If you have read our makharij al-huroof guide, you will recognise the groups: ت د ط from the tip of the tongue against the gum behind the upper front teeth, ث ذ ظ from the tip of the tongue against the edges of the upper front teeth, and ب م from the lips.

The cases you will meet in the Hafs recitation are:

• ت into ط: قَالَت طَّائِفَةٌ is read “qaalat-taa’ifatun” with one heavy ط held, not a light t and then a heavy t.
• د into ت: قَد تَّبَيَّنَ is “qat-tabayyana”. The daal disappears into a doubled taa.
• ت into د: أَثْقَلَت دَّعَوَا is “athqalad-da’awaa”.
• ذ into ظ: إِذ ظَّلَمُوا is “iẓ-ẓalamoo”, one doubled heavy ظ.
• ث into ذ: يَلْهَث ذَّٰلِكَ is “yalhadh-dhaalika”.
• ب into م: ارْكَب مَّعَنَا is “irkam-ma’anaa”. The lips close once, on a meem.

The one partial merge: ط into ت

There is one pair where the merge is only partial. In words like بَسَطتَ (basatta), أَحَطتُ (ahattu) and فَرَّطتُمْ (farrattum), the ط merges into the ت, but its heaviness stays. Your tongue goes to the ت, yet the mouth keeps the full, deep shape of the ط for that moment. Tajweed books call this idgham naqis, an incomplete merge. Reading it as a plain light “basatta” loses the ط completely; reading a full ط and then a ت ignores the merge. The right sound sits in between, and it is much easier to learn by hearing it than by reading about it. Our guide to heavy and light letters explains what that heaviness is.

Idgham mutaqaribain: close, but not the same

Here the two letters come from neighbouring points or share enough qualities that they blend. In Hafs there are two cases to know.

Lam into raa

قُل رَّبِّ is read “qur-rabbi”, and بَل رَّفَعَهُ اللّٰهُ is “bar-rafa’ahullaah”. The lam disappears and the raa is doubled. This comes up often because “qul” (say) appears so many times in the Quran.

One famous exception: in بَلْ ۜ رَانَ (Surah Al-Mutaffifin, 83:14) Hafs makes a tiny pause, called sakt, after “bal”, so the lam is read and there is no merge. The small س (seen) mark above the word tells you to pause without breathing.

Qaaf into kaaf

In أَلَمْ نَخْلُقكُّم (Surah Al-Mursalat, 77:20) the qaaf merges into the kaaf: “alam nakhlukkum”. The more common way in Hafs is a full merge. Some teachers also accept keeping a trace of the qaaf’s raised tongue, so follow the way your teacher reads it and stay consistent.

Why the merge happens at all

Try saying “qad tabayyana” quickly with a clear daal. Your tongue touches the same spot twice and stumbles. The merge is not decoration; it is the natural, easy way the Arabic was recited and passed down. That is also why the merged letter loses features it would normally have. A merged daal or baa does not get its qalqalah bounce, because it is not really pronounced anymore.

Mistakes we hear in class

• Bouncing a merged letter. “Qad-tabayyana” with a qalqalah on the daal, or “irkab-ma’anaa” with a popped baa. If the next letter has a shaddah, there is no bounce.
• Two letters where there should be one. “Qaalat taa’ifah” with a light t and then a heavy t.
• Losing the ط in basatta. The partial merge needs the ط’s weight.
• Merging at bal raan. Pause briefly instead.
• Merging across a stop. If you stop on the first word, there is no merge. These rules only apply when you join.

How to practise

1. Write the nine examples above on a card, with the Arabic and the way they are read.
2. Read each one slowly, then at your normal pace, with your finger on the shaddah.
3. Find “qul” followed by a raa in a few places in the 30th para and read them aloud.
4. Ask your teacher to say basatta and ahattu for you, and copy the sound three times.

This is an intermediate rule. If you are still working on the basics, start with Tajweed rules for beginners and our step-by-step guide on how to learn Tajweed online, then come back to it.

Learning with a teacher

Rules like the partial merge of ط are exactly where a live teacher saves you weeks. In our online Tajweed classes a teacher listens one-to-one for 30 minutes, five days a week (20 classes a month), and corrects each merge as you read. Classes run 24/7, with male and female teachers available at any time. As an online Quran institute we teach only Noorani Qaida, Nazra, Tajweed and Hifz. Fees are in the fee section: ₹4,000 a month, ₹21,000 for six months or ₹36,000 a year.

Idgham mutajanisain and mutaqaribain: FAQ

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