1-2-3 Inning – an inning where the pitcher faces three batters and none make it safely to a base

6-4-3 Double Play – a specific double play involving the shortstop (6), second baseman (4), and first baseman (3)—the shortstops grabs the ball and tosses it to the second baseman to force out the runner that’s advancing; the second baseman then tosses it to the first baseman to force out the batter

ACL – anterior cruciate ligament; the ACL stabilizes the knee and connects the upper leg to the lower leg by connecting to the femur and tibia

At-Bat – a completed plate appearance by a batter

Ball – a pitch that does not land inside the strike zone

Baseline – the line that runs between two bases on the baseball field

Baserunner – a player on the offensive team (the one currently batting) that has safely made it to base

Bases Loaded – runners on all three bases

Bat Bunny – a woman that wants to get with a baseball player; also known as a Baseball Annie

Batter’s Box – the rectanglular boxes on either side of home plate where the batter must be standing for fair play to resume

Batting Average – average number of hits a player has per at-bat

Batting Practice – a period usually before a game where players work on their batting technique

Blown Save – a charge a relief pitcher receives after they enter the game in a save situation and give up either the tying or winning run

Bottom of the Inning – the second half of an inning in which the home team bats

Bullpen – area used by pitchers and catchers to warm up and practice before taking the mound when play has already begun; usually off to the side of either the left or right side base line, or behind an outfield fence

Catch – when a fielder catches a batted ball in their glove or hand before it hits the ground and keeps possession of it until they release it

Catcher – the player that crouches behind home plate while the opposing team is at-bat; receives the pitches from the pitcher

Center Field – central part of the outfield, behind second base

Center Fielder – the outfielder that plays defense in the area of center field

Changeup – a pitch meant to look like a fastball but with less speed

Closer – relief pitcher that is used most often to close out the game by getting the final outs

Clubhouse – a team’s locker room

Complete Game – when a pitcher pitches the entire game himself without using a relief pitcher

Curveball – a pitch that curves from a straight path toward home plate

Designated Hitter – player who permanently bats in place of the pitcher

Double – a two-base hit

Double Play – a defensive play where two offensive players are forced out during continuous play, resulting in two outs

Dugout – where a team’s bench is located on the field; a depressed area slightly below field level

ERA – earned run average; the mean (average) of earned runs given up by a pitcher over nine innings

Error – a fielder’s misplay that allows a batter or baserunner to advance to one or more additional bases when that advance could have been avoided with ordinary effort

Fair Territory – the area of the playing field between the two foul lines

Farm System – affiliation of farm teams for each team; there are three levels in the farm system: A, AA, and AAA

Farm Team – a team affiliated with a specific professional team that provides experience and training for younger players with the expectation that successful players will move to the Major League at some point

Fastball – a pitch thrown more for speed than for movement; the most common type of pitch

Field Manager – the “head coach” of the team; controls the team strategy on the field

First Base – the base to the right of the pitcher when looking from home plate; the first base a baserunner needs to touch to score a run

First Baseman – the defensive player who fields the area closest to first base

Force Out – an out where a runner that is forced to advance is tagged out

Foul Ball – a ball that is batted into foul territory

Foul Lines – two straight lines drawn from home plate to the outfield separating fair territory and foul territory

Grand Slam – a home run hit with bases loaded; earns four runs

Ground Ball – a ball that bounces in the infield; also known as a grounder

Hit – the act of safely reaching base after hitting the ball into fair territory

Hit By Pitch – when a pitch hits the batter in the batter’s box; automatically advances to first base

Home Plate – where the batter stands, and the final base a runner must touch to score a run

Home Run – homer; a base hit where a batter is able to circle all the bases, usually done by hitting the ball into the stands or beyond

Infield – the square area within all 4 baselines

Infielder – a player stationed at one of the defensive infield positions between first and third base

Injured List – a way for teams to temporarily remove players from their active roster due to injury; another player is able to be called up to take their spot on the active roster; formerly called the Disabled List

IL – see Injured List

Inning – a unit of play consisting of two halves; there is the top of the inning (away team bats) and the bottom of the inning (home team bats); there are nine innings in a regular length baseball game

Knuckleball – a pitch thrown with no spin, usually with the knuckles; flutters and moves suddenly and erratically on its way to the plate

Leadoff Batter – leadoff hitter; the first batter in a team’s lineup

Left Field – part of outfield on the left of center field if looking from home plate

Left Fielder – the outfielder who plays defense in the area of left field

Line Drive – liner; a batted ball that is hit hard in the air and doesn’t have much arc

Mound – pitcher’s mound; raised section in the middle of the diamond used by the pitcher; area the pitcher stands to throw the pitch

MVP – Most Valuable Player; player that was instrumental to the team during the season, playoffs, or World Series

Netting – a large net separating the field from the stands, behind home plate and up the baselines, to prevent injury to spectators

No-Decision – when a starting pitcher doesn’t get either the win or the loss for the game

No-Hitter – a game where one team does not give up any hits; a player may still reach base by walk or error to earn a no-hitter; a no-hitter without any walks, hits, or errors is called a perfect game

Opening Day – the first day of the regular season

Outfield – the area of the field beyond the infield and between the foul lines

Outfielder – a player in one of three defensive positions in the outfield – left fielder, center fielder, and right fielder

Pitch Count – how many pitches a pitcher has thrown so far during a game

Pitching Coach – coach who works with pitchers on how to pitch, what pitch to throw, and how to throw them

Pop Out – when a player catches a pop up to get the player out

Pop Up – a fly ball that doesn’t travel far but does go high

Postgame – after the game has finished

Postseason – the playoffs

Relief Pitcher – reliever; a pitcher brought in to relieve another pitcher during a game

Right Field – part of outfield on the right of center field if looking from home plate

Right Fielder – the outfielder who plays defense in the area of right field

Run – a score in baseball when a player runs through all of the bases and makes it safely back to home plate; baseball scores are counted by runs

Save – when a relief pitcher, usually the closer, maintains the lead successfully until the end of the game; certain criteria must be met before a save is credited

Second Base – the base behind the pitcher; the second base a baserunner needs to touch to score a run

Second Baseman – the defensive player who fields the area closest to second base

Series – a set of games between two teams, typically three or four games in a row

Shortstop – the fielding position between second and third base; considered the most demanding defensive position

Single – a one-base hit

Skipper – Skip; field manager

Slider – fast pitch with a slight curve opposite to the direction of the throwing arm

Starting Pitcher – the first pitcher in the game for each team; starting pitchers are expected to pitch for a large part of each game, so they usually rest for three to five days between starts

Strength Training – weightlifting to increase strength and power and improve speed, agility, and coordination

Strike – when a batter doesn’t hit the ball when swinging; when a batter doesn’t swing at a pitch that lands in the strike zone; when a foul ball is hit with a strike count of less than two

Strike Zone – volume of space above home plate and between the batter’s knees and the middle of their torso; pitches that land here without the batter swinging count as a strike

Strikeout – three strikes in one plate appearance; qualifies as an out

Sweep – winning all the games in a series

Tag – when a fielder reaches to touch the baserunner either with a live ball or the glove holding a live ball; called a tag out when the fielder tags the baserunner before they reach the base

Third Base – the base to the left of the pitcher when looking from home plate; the third base a baserunner needs to touch to score a run

Third Baseman – the defensive player who fields the area closest to third base

Three Up, Three Down – when only three batters face a pitcher during an inning, meaning the three outs are obtained on the first three batters

Top of the Inning – the first half of an inning in which the away team bats

Triple – a three-base hit

Triple A – the highest level of play in Minor League Baseball; each team has an affiliated A, AA, and AAA team

Umpire – ump; in charge of the game; makes the calls on strikes, balls, fouls, catches, and when a batter safely makes it to base

WAG – abbreviation for wives and girlfriends; wives and girlfriends of the players

Walk – when a player advances to base after a pitcher throws four balls

Walk-Off – when the home team immediately wins the game when they score a run in the bottom of the final inning

World Series – the championship in major league baseball; a best of seven series to determine the best of the United States and Canada