Part of the marbles sport is the jargon, which must be adjusted for each individual neighborhood, but here is a good beginner's guide to terms:
For keeps: Playing without giving back your opponent's marble which you knock out of the ring.
For fair: Returning all your opponent's marbles at the end of the game. The decision to play for "keeps" or "fair" is decided by mutual consent at the beginning of each game. All games in the national tournament are for "fair."
Slip: A call made when your shooter slips from your hand and rolls a short distance, allowing you to shoot again. In most play the slip cannot roll within ten inches of the ring line.
Dubs: Hitting two or more marbles out of the ring with one shot.
Snooger: A close miss.
Kruckling down: Resting one or more knuckles on the ground when shooting.
Lofting (or popping): Shooting in an arc through the air to hit a marble.
Stick: When your shooter stops inside the ring line after hitting a marble out.
Bowling: Rolling, as opposed to shooting, your shooter across the ground. Generally, a novice technique.
Fudging: Raising one's hand from the ground when shooting, or
Hunching: Moving one's hand forward when shooting.
Eggies: Borrowed marbles or the act of borrowing marbles.
Spinning: The ability to make your shooter hit another marble making it travel while causing the shooter to lose momentum and stay in the ring or "stick."
Pot: The Hole.
Pitch and lag lines: Two parallel lines. At the beginning of play the participants toss their shooters at the lag line from the pitch line and whoever lands closest goes first.
Match: The agreed-upon number of games needed for a win. It can be one, three, five or any odd number of games.
These terms just scratch the surface in speaking Marble, but they should be enough to get you started.