Glossary of baseball (J) facts for kids

Baseball has many unique words and phrases. This section explains some of the terms that start with the letter 'J'.

Baseball Terms Starting with J

J-run

A "J-run" is when the pitcher runs from the pitcher's mound to first base. They do this to help cover the base. This usually happens if the first baseman has just caught the ball.

Jack

A "jack" is another word for a home run. It means hitting the ball so far that it goes out of the playing field. You might hear someone say, "He hit a jack!" or "He jacked that ball out of here!"

Jake

When a player makes a "jake" effort, it means they are playing lazily. They are not trying their hardest. For example, "He jaked that play" means he didn't give his full effort.

Jam

The word "jam" can mean a few things in baseball:

• Jamming a batter: A pitcher can "jam" a batter by throwing the ball very close to their body. This makes it hard for the batter to swing properly. It's like the pitch "handcuffed" or "shackled" them.
• Pitcher in a jam: A pitcher is "in a jam" when the other team has runners on base. This is especially true if runners are in scoring position and there are not many outs. It means the pitcher is in a tough spot and needs to get out of trouble.
• Bases jammed: When all three bases (first, second, and third) have runners on them, the "bases are jammed." This is also called "bases loaded" or "bases full."

Janitor Throw

A "janitor throw" happens when an outfielder tries to throw the ball very hard. But, they end up spinning around or falling down while throwing. It's a funny way to describe a throw that goes wrong.

Judy

A "Judy" is a type of Punch and Judy hitter. This is a player who hits the ball with very little power. They usually hit singles or ground balls instead of long hits or home runs.

Jump

The word "jump" can describe how quickly a player reacts:

• Good jump on the ball: A fielder gets a "good jump on the ball" when they react very quickly to a batted ball. This quick reaction helps them make a great play, like catching a fly ball or fielding a ground ball.
• Good jump as a baserunner: A baserunner gets a "good jump" when they start running from a base early. They leave the base well before the pitcher throws the ball to home plate. This helps them steal a base or advance on a hit.

Junior Circuit

The "Junior Circuit" is another name for the American League. It is called "junior" because it is younger than the National League. The American League started in 1901, while the National League began in 1876. The National League is known as the Senior Circuit.

Junk

In baseball, "junk" refers to certain types of pitches. These are usually breaking balls and knuckleballs. These pitches are hard to hit because they move in tricky ways, not because they are super fast. A pitcher who throws a lot of these pitches might be called a "junk pitcher." An example of a junk pitch is an Eephus pitch.

Junkball Pitcher

A "junkball pitcher" is a pitcher who mostly throws "junk" pitches. They often do this because their fastball isn't very fast. These pitchers rely on tricky movement and changing speeds to get batters out. They are also called a "junkballer" or a "junk artist."