Even a casual spectator will have enough basic knowledge of baseball's unique jargon to enjoy a game. But just in case you need a primer, here are a few terms — some more common than others — to keep you in the know at the ballpark.

• Around the horn: After an out, usually one recorded in the infield, the position players will toss the ball in a pattern around the infield, thus going “around the horn” with the baseball before throwing it back to the pitcher.

• Bases loaded: When a runner is at first, second and third base, the bases are loaded, giving the team at bat a solid chance to score.

• Can of corn: A fly ball that’s easy to catch, typically hit high and requiring little movement from the fielder who catches it.

• Grand slam: The most bang a single swing of bat can bring. A grand slam is a home run hit while the bases are loaded, scoring four runs total for the team at bat.

• Ground-rule double: You likely know what a double is — a hit that allows the batter to reach second base. A ground-rule double is a hit that lands somewhere in the field of play before bouncing over the fence into unplayable territory, resulting in the batter being awarded second base.

• Heater: Baseball pitchers have plenty of pitches in their arsenal from curveballs to splitters to sliders and even the occasional knuckleball. But no pitch is as tried and true as the heater, a fastball thrown all out for velocity.

• Sacrifice fly: A sacrifice fly is a fly ball that, despite being caught for an out, scores a runner.

• Seventh-inning stretch: Baseball isn’t a fast-paced pastime, with the average time of a game in the minor leagues coming in around 2 hours, 45 minutes. Don’t worry. A stretch period is built into the middle of the seventh inning. The break, a little longer than other between-inning reprieves, traditionally features a sing-along to “Take Me Out to the Ballgame,” but some teams opt for “God Bless America” or other well-known tunes.

• Squeeze: This is a sacrifice bunt laid down to score a runner from third base. The hitter expects to be thrown out first, thus sacrificing himself for the chance to get a run on the scoreboard.

• Turn two: When the defense gets two outs on one batted ball, the defense has turned two. While the phrase can be applied to any double play, it’s typically used when both outs take place at bases and involve more than one throw by the defense.