تقتضي تخصيص المكونات بوجه دون وجه، وفي وقت دون وقت
The attribute relates to specifying created things in one manner rather than another and at one time rather than another.
A possible entity can be considered under alternatives: existence or nonexistence, one size or color or another, earlier origination or later origination. Its being determined in a particular manner is called specification (takhṣīṣ).
The issue is not only whether existence is possible. It is why one definite possibility is actualized rather than the alternatives.