- The run the pitcher takes from the mound to first base in order to cover for the first baseman who has just fielded the ball.
- A home run or to hit a home run. "Hitting a jack" or "Jacking one out of here".
- Half-hearted or lazy effort by a player, i.e. "He jaked that play."
- To pitch far enough inside that the batter is unable to extend while swinging. "The pitcher jammed the batter." The batter was "handcuffed" or "shackled" by the pitch.
- When runners are in scoring position with less than two outs and good hitters coming up. "The pitcher is in a jam."
- The "bases are jammed" (or loaded or full) when there are runners on all three.
- When an outfielder, trying to throw hard, spins or falls down.
- A batter's legs are "made out of jelly" when he departs from a good stance. "His curve ball ... it jelly-legs you." - Phillies First Baseman Jim Thome, referring to Barry Zito's curve.
- To "pull" the ball towards left field if you bat right handed or "pull" the ball towards right field if you're batting left handed. Opposite of jerk would be push or hitting an "oppo", meaning going towards the opposite field.
- To hit the ball hard, typically used to refer to pulling the ball over the fence for a home run. "Derrek Lee jerked one of his patented doubles into the left-field corner to lead off the fourth against Minnesota lefty Johan Santana, the reigning Cy Young winner."
- A Punch and Judy hitter who hits with little power.
- "Bases juiced" means bases loaded.
- A player who is said to be juiced is thought to be taking performance-enhancing drugs. "It is now assumed, of course, that Bonds may well have been juiced on steroids at the time; the previous year he had set the all-time single-season record of 73 home runs, and his musculature was almost freakishly swollen."
- A baseball that is juiced has been modified in some way that makes it travel farther when hit. "Spectacular increases in home runs have often raised the question: Has the ball been juiced up to travel farther, in order to increase the number of home runs?"
- A fielder is said to get a good jump on the ball when he anticipates or reacts quickly to a batted ball and is thereby able to make a good play by fielding or catching it. Also see crack of the bat.
- A baserunner gets a good jump when he is able to leave the base well before the pitch reaches the plate. "Upsetting the timing of the baserunner can effectively prevent him from getting a good jump ... Base runners often read a pitcher's look and get their jump, or start, based on the pattern the pitcher establishes."
- The American League, so-called because it is the younger of the two major leagues. The American League was founded in 1901, while the National League – the Senior Circuit – was founded in 1876.
- breaking balls and knuckleballs, pitches that are hard to hit due to movement rather than velocity. "I couldn't believe he threw me a fastball because he had me down 1-2", Thames said. "He's usually a junk pitcher and he tried to sneak a fastball past me, and he left it up." See also: Eephus pitch
- A pitcher who throws predominantly junk, usually due to a weak (or slow) fastball. A junkballer or a junk artist: "Like all junk artists, Trujillo will have to prove himself at the higher levels before getting a shot at a major league job." See also: Eephus pitch
- "Barry Zito Quotes". www.baseball-almanac.com. Retrieved 2019-04-05.
- Rogers, Phil (2005-07-13). "American beauty". Chicago Tribune. Retrieved 2019-04-05.
- Robinson, Eugene (2007-12-18). "Fans on the Juice". The Washington Post. Retrieved 2019-04-05.
- Sowell, Thomas (2001-12-30). "Was the ball juiced?". Townhall. Retrieved 2019-04-05.
- See Allan R. Andrews, "A Good Jump on the Ball: Algorithm in the Outfield", The American Reporter (8 October 1998).
- Jack Stallings and Bob Bennett, Eds., Baseball Strategies: Your Guide to the Game within the Game, American Baseball Coaches Association, 2003, p. 125.
- "Granderson's homer, Thames' slam power Tigers' win". ESPN.com. 2007-07-07. Retrieved 2019-04-05.
- John Sickels Baseball Newsletter (June 15, 2001).