Śrī Jīva Goswami uses the terms viśeṣaṇa, upādhi and upalakṣaṇa routinely in the Sandarbhas. These terms carry a very specific meaning which we examine here.
A viśeṣaṇa is defined as –
kāryānvayitve sati kāryakāle vartamānatve sati vyāvartakatvam – That which is a part of the object, is always present when the object is present, and distinguishes the object from others.
An upādhi is defined as –
kāryānanvayitve sati kāryakāle vartamānatve sati vyāvartakatvam – That which is not part of the object, is always present when the object is present, and distinguishes the object from others.
An upalakṣaṇa is defined as –
kādaciktve sati vyāvartakatvam – That which is only present sometimes, and distinguishes the object from others.
As an example, consider that we wish to communicate the location of a building to someone who is looking for it and is just across the street from it. We may point to the building, and say, “see that building made of red brick, having four floors, and a dark brown door?” The red brick, four floors, and dark brown door are examples of a viśeṣaṇa.
Now we may point to a tall tree next to the building, and say, “see that building next that tall tree?”. The tree is an example of an upādhi – it is not part of the building, but is always present next to it.
Finally, there may be a blue car parked in front of the building. We may say, “see that building with the blue car in front of it?”. The blue car is an upalakṣaṇa of the building. The car is not a part of the building and is not going to be always present next to the building.
These technical words are used to great effect in the Sandarbhas.