Pratishthaa is derived from Prati and Sthaa, means to stay, means the act of making anything, stand firmly, establishing firmly.

(1) Respect.
(2) Installation.  Idol worship is very common in Hindoo religion. But every idol is not to be worshipped. When it is established in temples, it needs Pratishthaa. Pratishthaa means "to request god to come and live in that idol so that we can worship him". It is because we do not worship just idol, we worship it as the image of God. And to make it an image of God we will have to perform some ceremonies. When it is kept in houses, it takes time, for example we daily worship it, we treat it as our God, then only it turns into an image of God. So Pratishthaa is a process in which an idol is turned into an image of God.

(3) Any good work is started by worshipping God, so the the worship done to start that work is also called Pratishthaa. By doing this worship we wish that "our work finishes without obstacles, and it should be for the welfare".