arthāpattiḥ
Presumption; assumption of a thing not itself perceived but implied by what is perceived - a pramāṇam.
In Vedanta
Postulation — the means of knowledge by which one arrives at an otherwise unexplained fact. For example, if Devadatta is alive but not at home, one postulates he is elsewhere. In Vedānta, arthāpatti can support understanding — for instance, if Brahman is the cause of everything and is consciousness, one postulates that the material world is not separate from consciousness.