أَمَّا الْمَعْنَوِيَّةُ: فَهِيَ أَنْ يَكُونَ الْمُضَافُ غَيْرَ صِفَةٍ مُضَافَةٍ إِلَى مَعْمُولِهَا.
Translation: Semantic iḍāfah is a construction in which the mudāf is not a descriptive word attached to its own syntactic dependent.
In غُلَامُ زَيْدٍ, ghulām expresses belonging; it is not an active descriptor governing Zayd as an object.
خَاتَمُ فِضَّةٍ and صَلَاةُ اللَّيْلِ also belong to this type, although their implied relationships differ.