Terms — Snooker

Baulk Line & D
Line and semicircle at the baulk end from which break‑off is played.
Ball‑On
Any ball that may legally be struck first on the current shot.
Break
Consecutive points scored in one visit.
Break‑Off
Opening shot of a frame from within the D.
Cannon
Cue ball caroms off two balls on the same shot.
Free Ball
After a foul leaves a total snooker, the next player may nominate any ball as a red for one point.
In‑Off
Cue ball is pocketed after contacting another ball; counts as a foul.
Miss (Foul‑and‑a‑Miss)
If a player could have hit the ball‑on but didn’t, the referee may call a miss; the shot can be replayed.
Plant
Combination shot in snooker.
Respotted Black
When scores tie at the end of a frame, black is re‑spotted for a tiebreak.
Safety Exchange
Series of tactical shots seeking a mistake or a snooker.
Snooker
When direct path to any ball‑on is blocked by other balls.
Spider / Rest
Bridges used to extend reach; spider has high legs for clearance.
Touching Ball
When the cue ball is touching a ball‑on; special play requirements apply.