Judging by the similarity of the texts of Vat. and March. and the original usage of مفعوﻻت (not as a litteral rendering of a Latin plural, it should not be earlier than a wide circulation of the scientific treatises abundant with such constructions. Sibawayh in his grammar still uses e.g. ثلاثة مفعولين instead of مفعوﻻت ...
