Mutajānisayn are different consonants classified at the same articulation place. In وَقَالَتْ طَائِفَةٌ, the tāʾ and ṭāʾ form the example.
The defining point is their articulatory relationship, not simply that they “sound similar.” Assimilation changes the junction; preserve the reading as transmitted instead of forcing an independent release of the earlier tāʾ.
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Mutajānisayn: shared articulation
Idghām: Types, Complete/Incomplete Assimilation and the Definite Article
Mutajānisayn are different consonants classified at the same articulation place. In وَقَالَتْ طَائِفَةٌ, the tāʾ and ṭāʾ form the example.
The defining point is their articulatory relationship, not simply that they “sound similar.” Assimilation changes the junction; preserve the reading as transmitted instead of forcing an independent release of the earlier tāʾ.