What is the meaning of Onside?

Not in an offside position; In the part of the playing area where one can legally play the ball, puck, etc.

Within bounds.

On the side of a vehicle from which the driver, paddler, etc. propels it.

Favourably located, from the point of view of the player taking a finesse.

In agreement or support; on board.

The portion of the playing area where one can legally play the ball, puck, etc.

The side of a vehicle on which the driver primarily propels it.

Source: wiktionary.org