Baseball terms explained
Plain-English definitions of the baseball and softball terms players, parents and new fans hear most, from slang like a can of corn to stats like slugging percentage and the bat standards on every barrel. Each term links to our full guide.
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- 3-0 count
Three balls and no strikes. One more ball is a walk, so the pitcher usually throws a strike, and many hitters take the pitch unless the coach gives them the green light to swing.
B
- Balk
An illegal motion by the pitcher with runners on base, such as starting the delivery and stopping or not coming set. Every runner advances one base.
- Base on balls (BB)
BB is the scorebook abbreviation for a base on balls, better known as a walk: the batter goes to first base after four pitches outside the strike zone.
- Batboy
A team helper, often a teenager, who collects bats after each at-bat, keeps the umpire supplied with baseballs and helps the dugout run smoothly.
- Batter’s box
The two chalked rectangles, one on each side of home plate, where the batter stands. In MLB each is 4 feet wide and 6 feet long, and hitting the ball with a foot entirely outside the box is an out.
- Batting average
Hits divided by official at-bats. Walks, hit-by-pitches and sacrifices don’t count as at-bats, and .300 is the classic mark of a strong hitter.
- BBCOR
Batted Ball Coefficient of Restitution, the standard non-wood bats must meet in high school and college baseball. BBCOR bats have a -3 drop and a barrel no wider than 2 5/8 inches.
- Big barrel bat
A youth bat with a barrel wider than 2 5/8 inches, usually 2 3/4 inches. Allowed in USSSA travel ball, but not in Little League.
- Blue
Players’ and coaches’ nickname for the umpire, from the dark blue uniforms umpires have worn since the late 1800s.
- Box seats
Premium lower-level seats close to the field, usually along the baselines or behind home plate. Many come with in-seat service or lounge access.
C
- Can of corn
An easy, lazy fly ball that a fielder catches without having to move much. The phrase is usually credited to old grocers knocking cans off high shelves and catching them.
- Charging the mound
When a batter, usually after being hit or brushed back by a pitch, runs at the pitcher to fight. It typically empties both benches and leads to ejections and suspensions.
- Chin music
A high, inside fastball thrown near the batter’s chin to back them off the plate, also called a brushback pitch. Pitching inside is legal; throwing at a batter on purpose can get the pitcher ejected.
D
- Day-to-day (DTD)
The injury status for a player who is hurt but expected back within a few days, without being placed on the injured list.
- Dinger
Slang for a home run. You’ll also hear tater, bomb, jack and moonshot.
- Double steal
A play in which two runners each steal a base on the same pitch, most often with runners on first and third or on first and second.
- Drop weight
A bat’s length in inches minus its weight in ounces. A 32-inch, 22-ounce bat is a drop 10 (-10); the bigger the drop, the lighter the bat.
- Dropped third strike
If the catcher doesn’t cleanly catch strike three, the batter can run to first, as long as first base is open or there are two outs.
E
- Error
A misplay the official scorer charges to a fielder, like a dropped throw or bobbled grounder, that lets a batter reach or a runner advance when ordinary effort would have made the play. Runs that score because of errors are unearned.
F
- Fifth infielder
A shift, usually with the winning run on third late in a game, where an outfielder moves into the infield to cut off a ground ball.
- Forfeit
A game awarded to one team, officially 9-0, when the other team refuses to play, can’t field enough players or breaks certain rules. Forfeits are very rare in pro baseball.
- Fourth out
An out recorded after the third out to cancel a run, usually on an appeal: if a runner missed a base or left early on a caught fly, the defense can still appeal and take the run off the board.
- Full count
Three balls and two strikes. The next pitch ends the at-bat with a walk, strikeout or ball in play, unless the batter fouls it off.
- Fungo bat
A long, thin, light bat that coaches use to hit fly balls and grounders during fielding practice.
G
- Ground rule double
When a fair ball bounces over the outfield fence or out of play, the batter is awarded second base and every runner advances two bases.
H
- Hit by pitch (HBP)
When a pitch touches a batter who isn’t swinging, the batter is awarded first base, unless the ball was in the strike zone or the batter made no attempt to avoid it.
I
- Immaculate inning
A half-inning in which a pitcher strikes out all three batters on nine pitches, every one of them a strike.
- In the hole
Most often, the batter due up after the on-deck hitter: at bat, on deck, then in the hole. It also means the gap between the shortstop and third baseman, or a pitcher or hitter who has fallen behind in the count.
L
- Live-ball era
Baseball since about 1920, when scoring and home runs rose sharply after the spitball was banned and dirty balls were replaced more often. It followed the dead-ball era.
M
- Magic number
The number of wins by a leading team, or losses by its closest rival, needed to clinch a division or playoff spot. Each one lowers it by one; at zero the team has clinched.
- Mercy rule
A rule that ends a game early when one team leads by a set margin after a set number of innings, such as 10 runs after five. Common in youth, high school and college ball; MLB doesn’t use it.
P
- Pennant race
The late-season chase for a league championship, the pennant, whose winner goes to the World Series. Today it usually means the race for division titles and playoff spots.
- Pinch runner
A substitute who replaces a player on base, usually for speed late in a close game. In MLB the replaced player can’t return.
- Pine tar
A sticky resin hitters rub on the bat handle for grip. MLB allows it only on the bottom 18 inches of the bat.
- Pitch clock
A timer that limits the time between pitches. In MLB it is 15 seconds with the bases empty and 18 with runners on; a pitcher violation is an automatic ball and a batter violation an automatic strike.
Q
- Quality at-bat (QAB)
A coaching stat that rewards a good at-bat, not just a hit: a hard-hit ball, a walk, a long at-bat of six or more pitches, moving a runner or a sacrifice.
R
- Raking
Slang for hitting the ball hard and often. A hitter who is raking is on a hot streak.
- Retire the side
“The side” is the team batting in a half-inning; retiring the side means getting three outs. Striking out the side means all three outs came by strikeout.
S
- Slapper
A fastpitch hitter, usually left-handed, who slaps or bunts the ball while already moving toward first base to make use of their speed.
- Slugging percentage
Total bases divided by at-bats: a single counts 1, a double 2, a triple 3 and a home run 4. It measures power, while batting average treats every hit the same.
- Slump
A stretch when a player performs well below their usual level, most often a hitter who goes many at-bats without a hit.
- Stolen base (SB)
SB is the scorebook abbreviation for a stolen base: a runner takes the next base during a pitch without the help of a hit, walk or error.
T
- Throwing out the first pitch
The ceremonial first pitch: before the game, a guest of honor throws a pitch to a player, usually the catcher. It doesn’t count in the game.
- Tie goes to the runner
The saying that when the runner and the ball arrive at the same moment, the runner is safe. The rulebook calls a runner out only if the base is tagged before the runner reaches it, which is where the saying comes from.
- Triple Crown
Leading the league in batting average, home runs and RBIs in the same season. Pitchers win it by leading in wins, strikeouts and ERA.
- Triple-double (unofficial)
Not an official baseball stat. Fans borrow the basketball term for a season with double digits in doubles, triples and home runs. The closest real feat is the 20-20-20-20 club, which only four players have reached.
- Turf shoes
Training shoes with small rubber nubs instead of spikes, made for artificial turf, batting cages and coaching on the field.
U
- USA Baseball bat (USABat)
The bat standard required since 2018 by Little League, Babe Ruth, Cal Ripken and other youth leagues. These bats perform close to wood and carry the USA Baseball stamp.
- USSSA bat
A bat certified for USSSA and many travel ball tournaments, marked with the 1.15 BPF stamp. USSSA allows lighter drops and barrels up to 2 3/4 inches.
- Utility player
A player who can handle several positions, usually around the infield and sometimes the outfield, and fills in wherever the team needs.
W
- Walk-off
A hit, walk or other play that ends the game with the home team winning in its final at-bat, so the players walk off the field.
- Wild card
A playoff spot for a team that didn’t win its division but had one of the best remaining records. Since 2022 each MLB league has three wild card teams.