Without iḍāfah: مُسْلِمُونَ (sound masculine plural, nominative).
In iḍāfah, the final nūn drops: مُسْلِمُو + yāʾ.
The book changes the plural wāw to yāʾ and assimilates the yāʾs → مُسْلِمِيَّ.
This is a plural suffix transformation, unlike the lexical final yāʾ of qāḍin.
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Iḍāfah to Yāʾ al-Mutakallim and the Six Nouns
Without iḍāfah: مُسْلِمُونَ (sound masculine plural, nominative).
In iḍāfah, the final nūn drops: مُسْلِمُو + yāʾ.
The book changes the plural wāw to yāʾ and assimilates the yāʾs → مُسْلِمِيَّ.
This is a plural suffix transformation, unlike the lexical final yāʾ of qāḍin.