A property of Pudgala (physical substance) in the form of mode of mass (or weight); it is a property of that physical substance, which is in the form of a gross Skandha (aggregate).
(Bhaga 2.45)
gurtdaghudravyāṇi bādaraskandhadravyāṇi......tatparyavāḥ.
(Jaṃ Vṛ Pa 130)