An open circuit is called open because the circuit has an opening, a disconnection. In other words, there is an open space in the circuit in which the electrons cannot move through.

An open circuit....

When a circuit is in off condition then it is called an open circuit..

No.

An open circuit is any CIRCUIT (from circle) which is not closed.

That is; any break in the circle (circuit) makes it an open circuit.

As load is conected in circuit , so thre is no open circuit therefore there would not be any open circuit voltage.