Originally Kanmotsu is thought to have been the term for Denso (rice field tax), a property tax, but after the Ritsuryo system was established, 'Kanmotsu' became the term to describe tithes such as Soyocho and suiko (government loans), shozei (the rice tax stored in a provincial office's warehouse) and its use and accumulated products.
本来は地税である田租を指して官物と呼んだと考えられているが、律令制以後には租庸調をはじめとする貢納物や出挙・正税などのその運用・集積物を含めて「官物」と呼ばれるようになった。