onside
adjectiveUK /ˌɒnˈsaɪd/
US /ˌɑːnˈsaɪd/
In a game, being in a spot where the rules say you are allowed to be.
The referee said the player was onside, so the goal counted.
OTHER MEANINGS
2. In soccer, a position where an attacking player is not closer to the goal line than the ball and the second-to-last defender.
The striker timed her run perfectly to stay onside.
3. In American football, a kick that travels the required distance and can be recovered by the kicking team.
They tried an onside kick to get the ball back.
4. On the side of a vehicle closest to the road or curb.
He opened the onside door carefully before stepping out.