See s.v. ˁwd note.
In Syriac the prepositional usage has almost been totally replaced by ܥܕܡܐ, but even in those cases where simple ܥܕ precedes a noun or adjective there is an element of conjunctivity to the usage: "while being" or the like; see s.v. ˁd conj.
Similarly in Mandaic alma l- is far more common (for which also see s.v. ˁdmˀ prep.