What is a possessive phrase (murakkab idafi)?
In one line
Classical definition
Understand it
Two nouns stand side by side and the second explains the first. The first is the مُضَاف (mudaf); the second is the مُضَاف إِلَيْه (mudaf ilayh).
The two parts
Every idafa has exactly two parts: the mudaf, which loses its tanwin, and the mudaf ilayh, which is always majrur.
In كِتَابُ مُحَمَّدٍ (kitabu muhammadin), “Muhammad’s book”, كِتَاب is the mudaf and مُحَمَّد is the mudaf ilayh. The mudaf loses its tanwin, and the mudaf ilayh takes a kasra — it is always majrur.
A hidden preposition is what the relation stands on. بَابُ خَشَبٍ (babu khashabin) means a door of wood. صِيَامُ النَّهَارِ (siyamu al-nahari) means fasting in the day. كِتَابُ مُحَمَّدٍ means the book belonging to Muhammad.
How to spot it
In the Qur'an
In the language — فِي اللُّغَة
The word إِضَافَة (idafa) in everyday Arabic means adding one thing to another.
أَضَافَ ضَيْفًا (adafa dayfan) — “he took in a guest”
As a grammatical term it means joining one noun to another so that the second defines the first.
Common questions
Is idafa the same as an apostrophe-s in English?
It covers that and more. Possession is only one of its meanings: the second noun can also say what a thing is made of, where it belongs, or what kind it is. The grammar stays constant even when the meaning shifts — the first word drops ال and tanwin, the second is in jarr.
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