Note: Rule numbers in blue (like this: 3.06) follow the new OBR rule and numbering scheme introduced in the 2015 Official Baseball Rules. The rule numbers in red brackets (like this: [3.04]) are corresponding rule numbers from the Official Rules prior to 2015. All of the content has been updated to the 2016 rule book.
ADJUDGED is a judgment decision by an umpire.
APPEAL is an act of a fielder in claiming violation of the rules by the offensive team.
BALK is an illegal act by the pitcher with a runner or runners on base, entitling all runners to advance one base.
BALL is a pitch which does not enter the strike zone in flight and is not struck at by the batter. If the pitch touches the ground and bounces through the strike zone it is a "ball." (Rule 3.01 Comment).
BASE is one of four points which must be touched by a runner in order to score a run; more usually applied to the canvas bags and the rubber plate which mark the base points.
BASE COACH is a team member in uniform who is stationed in the coach’s box at first or third base to direct the batter and the runners.
BASE ON BALLS is an award of first base granted to batters who, during their time at bat, receive four pitches outside the strike zone.
BATTER is an offensive player who takes a position in the batter's box.
BATTER-RUNNER (BR) is a term that identifies the offensive player who has just finished a time at bat until that player is put out or until the play on which that player becomes a runner ends.
BATTER'S BOX is the area within which the batter must stand during a time at bat. See 5.04(b)(4) (Batter's Box Rule).
BATTERY is the pitcher and catcher.
BENCH (or DUGOUT) is the seating facilities reserved for players, substitutes and other team members in uniform when they are not actively engaged on the playing field.
BUNT is a batted ball not swung at, but intentionally met with the bat and tapped slowly within the infield.
CALLED GAME is one in which, for any reason, the umpire-in-chief terminates play.
CATCH is the act of a fielder in getting secure possession in his hand or glove of a ball in flight and firmly holding it; providing he does not use his cap, protector, pocket or any other part of his uniform in getting possession. It is not a catch, however, if simultaneously or immediately following his contact with the ball, he collides with a player, or with a wall, or if he falls down, and as a result of such collision or falling, drops the ball. It is not a catch if a fielder touches a fly ball which then hits a member of the offensive team or an umpire and then is caught by another defensive player. In establishing the validity of the catch, the fielder shall hold the ball long enough to prove that he has complete control of the ball and that his release of the ball is voluntary and intentional. If the fielder has made the catch and drops the ball while in the act of making a throw following the catch, the ball shall be adjudged to have been caught.
(Catch) Comment: A catch is legal if the ball is finally held by any fielder, even though juggled, or held by another fielder before it touches the ground. Runners may leave their bases the instant the first fielder touches the ball. A fielder may reach over a fence, railing, rope or other line of demarcation to make a catch. He may jump on top of a railing, or canvas that may be in foul ground. No interference should be allowed when a fielder reaches over a fence, railing, rope or into a stand to catch a ball. He does so at his own risk.
If a fielder, attempting a catch at the edge of the dugout, is “held up” and kept from an apparent fall by a player or players of either team and the catch is made, it shall be allowed.
CATCHER is the fielder who takes the position back of the home base.
CATCHER'S BOX is that area within which the catcher shall stand until the pitcher delivers the ball.
CLUB is a person or group of persons responsible for assembling the team personnel, providing the playing field and required facilities, and representing the team in relations with the league.
COACH is a team member in uniform appointed by the manager to perform such duties as the manager may designate, such as but not limited to acting as base coach.
DEAD BALL is a ball out of play because of a legally created temporary suspension of play.
DEFENSE (or DEFENSIVE) is the team, or any player of the team, in the field.
DOUBLE HEADER is two regularly scheduled or rescheduled games, played in immediate succession.
DOUBLE PLAY is a play by the defense in which two offensive players are put out as a result of continuous action, providing there is no error between putouts.
(a) force double play is one in which both putouts are force plays.
(b) reverse force double play is one in which the first out is a force play and the second out is made on a runner for whom the force is removed by reason of the first out. Examples of reverse force plays: runner on first, one out; batter grounds to first baseman, who steps on first base (one out) and throws to second baseman or shortstop for the second out (a tag play). Another example: bases loaded, none out; batter grounds to third baseman, who steps on third base (one out); then throws to catcher for the second out (tag play).
DUGOUT (see bench)
FAIR BALL is a batted ball that settles on fair ground between home and first base, or between home and third base, or that is on or over fair territory when bounding to the outfield past first or third base, or that touches first, second or third base, or that first falls on fair territory on or beyond first base or third base, or that, while on or over fair territory touches the person of an umpire or player, or that, while over fair territory, passes out of the playing field in flight.
A fair fly shall be judged according to the relative position of the ball and the foul line, including the foul pole, and not as to whether the fielder is on fair or foul territory at the time he touches the ball.
(Fair Ball) Comment: If a fly ball lands in the infield between home and first base, or home and third base, and then bounces to foul territory without touching a player or umpire and before passing first or third base, it is a foul ball; or if the ball settles on foul territory or is touched by a player on foul territory, it is a foul ball. If a fly ball lands on or beyond first or third base and then bounces to foul territory, it is a fair hit.
A batted ball not touched by a fielder, which hits the pitcher’s rubber and rebounds into foul territory, between home and first, or between home and third base is a foul ball. (See Foul Ball (Comment).)
Clubs, increasingly, are erecting tall foul poles at the fence line with a wire netting extending along the side of the pole on fair territory above the fence to enable the umpires more accurately to judge fair and foul balls.
FAIR TERRITORY is that part of the playing field within, and including the first base and third base lines, from home base to the bottom of the playing field fence and perpendicularly upwards. All foul lines are in fair territory.
FIELDER is any defensive player. (See defense.)
FIELDER'S CHOICE is the act of a fielder who handles a fair grounder and, instead of throwing it to first base to put out the batter-runner, throws to another base in an attempt to put out a preceding runner. The term is also used by scorers (a) to account for the advance of the batter-runner who takes one or more extra bases when the fielder who handles the safe hit attempts to put out a preceding runner; (b) to account for the advance of a runner (other than by stolen base or error) while a fielder is attempting to put out another runner; and (c) to account for the advance of a runner made solely because of the defensive team's indifference (i.e., undefended steal).
FLY BALL is a batted ball that goes high in the air in flight.
FORCE PLAY is a play in which a runner legally loses the right to occupy a base by reason of the batter becoming a runner.
Comment: Confusion regarding this play is removed by remembering that frequently the "force" situation is removed during the play.
Example: Runner on first, one out, ground ball hit sharply to first baseman, who touches the base and the batter-runner is out. The force is removed at that moment and the runner advancing to second must be tagged. If there had been a runner at second or third, and either of these runners scored before the tag-out at second, the run(s) would count. Had the first baseman thrown to second and the ball had been returned to first, the play at second would have been a force-out, making two outs, and the return throw to first would have made the third out. In that case, no run would score.)
Example: Not a force out. One out. Runner on first and third. Batter flies out. Two out. Runner on third tags up and scores. Runner on first tries to retouch before throw from fielder reaches first baseman, but does not get back in time and is out. Three outs. If, in umpire’s judgment, the runner from third touched home before the ball was held at first base, the run counts.
FORFEITED GAME is a game declared ended by the umpire-in-chief in favor of the offended team by the score of 9 to 0, for violation of the rules.
FOUL BALL is a batted ball that settles on foul territory between home and first base, or between home and third base, or that bounds past first or third base on or over foul territory, or that first falls on foul territory beyond first or third base, or that while on or over foul territory, touches the person of an umpire or player, or any object foreign to the natural ground.
A foul fly shall be judged according to the relative position of the ball and the foul line, including the foul pole, and not as to whether the fielder is on foul or fair territory at the time that fielder touches the ball.
Comment: A batted ball not touched by a fielder, which hits the pitcher’s rubber and rebounds into foul territory, between home and first, or between home and third base is a foul ball.
If a fly ball lands in the infield between home and first base, or home and third base, and then bounces to foul territory without touching a player or umpire and before passing first or third base, it is a foul ball; or if the ball settles on foul territory or is touched by a player on foul territory, it is a foul ball. If a fly ball lands on or beyond first or third base and then bounces to foul territory, it is a fair hit. (See Fair Ball (Comment).)
FOUL TERRITORY is that part of the playing field outside the first and third base lines extended to the fence and perpendicularly upwards.
FOUL TIP is a batted ball that goes sharp and direct from the bat to the catchers hands and is legally caught. It is not a foul tip unless caught and any foul tip that is caught is a strike, and the ball is in play. It is not a catch if it is a rebound, unless the ball has first touched the catcher's glove or hand.
GROUND BALL is a batted ball that rolls or bounces close to the ground.
HOME TEAM is the team on whose grounds the game is played, or if the game is played on neutral grounds, the home team shall be designated by mutual agreement.
ILLEGAL (or ILLEGALLY) is contrary to these rules.
ILLEGAL PITCH is (1) a pitch delivered to the batter when the pitcher does not have the pivot foot in contact with the pitcher's plate; (2) a quick return pitch. An illegal pitch with runners on base is a balk.
INFIELDER is a fielder who occupies a position in the infield.
INFIELD FLY is a fair fly ball (not including a line drive nor an attempted bunt) which can be caught by an infielder with ordinary effort, when first and second, or first, second and third bases are occupied, before two are out. The pitcher, catcher and any outfielder stationed in the infield on the play shall be considered infielders for the purpose of this rule.
When it seems apparent that a batted ball will be an Infield Fly, the umpire shall immediately declare "Infield Fly" for the benefit of the runners. If the ball is near the baseline, the umpire shall declare "Infield Fly if Fair."
The ball is alive and runners may advance at the risk of the ball being caught, or retouch and advance after the ball is touched, the same as on any fly ball. If the hit becomes a foul ball, it is treated the same as any foul.
If a declared Infield Fly is allowed to fall untouched to the ground, and bounces foul before passing first or third base, it is a foul ball. If a declared Infield Fly falls untouched to the ground outside the baseline, and bounces fair before passing first or third base, it is an Infield Fly.
(Infield Fly) Comment: On the infield fly rule the umpire is to rule whether the ball could ordinarily have been handled by an infielder—not by some arbitrary limitation such as the grass, or the base lines. The umpire must rule also that a ball is an infield fly, even if handled by an outfielder, if, in the umpire’s judgment, the ball could have been as easily handled by an infielder. The infield fly is in no sense to be considered an appeal play. The umpire’s judgment must govern, and the decision should be made immediately.
When an infield fly rule is called, runners may advance at their own risk. If on an infield fly rule, the infielder intentionally drops a fair ball, the ball remains in play despite the provisions of Rule 5.09(a)(12). The infield fly rule takes precedence.
If interference is called during an Infield Fly, the ball remains alive until it is determined whether the ball is fair or foul. If fair, both the runner who interfered with the fielder and the batter are out. If foul, even if caught, the runner is out and the batter returns to bat.
IN FLIGHT describes a batted, thrown, or pitched ball which has not yet touched the ground or some object other than a fielder.
IN JEOPARDY is a term indicating that the ball is in play and an offensive player may be put out.
INNING is that portion of a game within which the teams alternate on offense and defense and in which there are three putouts for each team. Each team's time at bat is a half-inning.
(a) Offensive interference is an act by a member of the team at bat which interferes with, obstructs, impedes, hinders or confuses any fielder attempting to make a play.
(b) Defensive interference is an act by a fielder which hinders or prevents a batter from hitting a pitch.
(c) Umpire's interference occurs (1) when an umpire hinders, impedes or prevents a catcher's throw attempting to prevent a stolen base or retire a runner on a pick-off play, or (2) when a fair ball touches an umpire on fair territory before passing a fielder.
(d) Spectator interference occurs when a spectator reaches out of the stands and over the playing field, or goes on the playing field, and (1) touches a live ball or (2) touches a player and hinders an attempt to make a play on a live ball
LEAGUE is a group of clubs who play each other in a pre-arranged schedule under these rules for the league championship.
LEAGUE PRESIDENT is the league official charged with enforcing these Rules, fining or suspending any player, manager, coach or umpire for violation of these Rules, resolving any disputes involving these Rules or determining any protested games.
(League President) Comment: With respect to the Major Leagues, the functions of the League President pursuant to these Rules shall be carried out by the designees of the Commissioner of Baseball. The Commissioner may designate different officials to carry out different functions of a League President pursuant to these Rules.
LEGAL (or LEGALLY) is in accordance with these rules.
LINE DRIVE is a batted ball that goes sharp and direct from the bat to a fielder without touching the ground.
LIVE BALL is a ball which is in play.
MANAGER is a person appointed by the club to be responsible for the team’s actions on the field, and to represent the team in communications with the umpire and the opposing team. A player may be appointed manager.
OBSTRUCTION is the act of a fielder who, while not in possession of the ball and not in the act of fielding the ball, impedes the progress of any runner.
OFFENSE is the team, or any player of the team, at bat.
OFFICIAL SCORER See Rule 9.00 (not available on this site).
ORDINARY EFFORT is the effort that a fielder of average skill at a position in that league or classification of leagues should exhibit on a play, with due consideration given to the condition of the field and weather conditions.
Comment: This standard, called for several times in the Official Scoring Rules (e.g., Rules 9.05(a)(3) (Rule 10.05(a)(3)), 9.05(a)(4) (Rule 10.05(a)(4)), 9.05(a)(6) (Rule 10.05(a)(6)), 9.05(b)(3) (Base Hits) (Rule 10.05(b)(3) (Base Hits)); 9.08(b) (Sacrifices) (Rule 10.08(b)) (Sacrifices)); 9.12(a)(1) Comment ((Rule 10.12(a)(1) Comment), 9.12(d)(2) (Errors) ((Rule 10.12(d)(2) (Errors)); and 9.13(a), 9.13(b) (Wild Pitches and Passed Balls) (Rule 10.13(a)), 10.13(b) (Wild Pitches and Passed Balls)) and in the Official Baseball Rules (e.g., Definition of Terms, Infield Fly), is an objective standard in regard to any particular fielder. In other words, even if a fielder makes his best effort, if that effort falls short of what an average fielder at that position in that league would have made in a situation, the official scorer should charge that fielder with an error.
OUT is one of the three required retirements of an offensive team during its time at bat.
OUTFIELDER is a fielder who occupies a position in the outfield, which is the area of the playing field most distant from home base.
OVERSLIDE (or OVERSLIDING) is the act of an offensive player when the slide to a base, other than when advancing from home to first base, is with such momentum that the player loses contact with the base.
PENALTY is the application of these rules following an illegal act.
PERSON of a player or an umpire is any part of his body, his clothing or his equipment.
PITCH is a ball delivered to the batter by the pitcher.
Comment: All other deliveries of the ball by one player to another are thrown balls.
PITCHER is the fielder designated to deliver the pitch to the batter.
PIVOT FOOT is that foot of the pitcher which is in contact with the pitcher's plate as he delivers the pitch. (The pivot foot for a right-handed pitcher is the right foot; for a left-handed pitcher, the left foot.)
"PLAY" is the umpire's order to start the game or to resume action following any dead ball.
QUICK RETURN ("quick pitch") is a pitch made with obvious intent to catch a batter off balance. It is an illegal pitch.
REGULATION GAME. See Rule 7.01.
RETOUCH is the act of a runner returning to a base as legally required. Also called TAG-UP.
RUN (or SCORE) is the score made by an offensive player who advances from batter to runner and touches first, second, third and home bases in that order.
RUN-DOWN is the act of the defense in an attempt to put out a runner between bases.
RUNNER is an offensive player who is advancing toward, or touching, or returning to any base.
"SAFE" is a declaration by the umpire that a runner is entitled to the base for which that runner was trying.
SET POSITION is one of the two legal pitching positions (the other being the windup position).
SQUEEZE PLAY is a term to designate a play when a team, with a runner on third base, attempts to score that runner by means of a bunt.
STRIKE is a legal pitch when so called by the umpire, which —
(a) Is struck at by batter and is missed;
(b) Is not struck at, if any part of the ball passes through any part of the strike zone;
(c) Is fouled by the batter when he has less than two strikes;
(d) Is bunted foul;
(e) Touches the batter as he strikes at it;
(f) Touches the batter in flight in the strike zone; or
(g) Becomes a foul tip.
STRIKE ZONE The STRIKE ZONE is that area over home plate the upper limit of which is a horizontal line at the midpoint between the top of the shoulders and the top of the uniform pants, and the lower level is a line at the hollow beneath the kneecap. The Strike Zone shall be determined from the batter’s stance as the batter is prepared to swing at a pitched ball. (For diagram of STRIKE ZONE see Appendix 5.)
SUSPENDED GAME is a called game which is to be completed at a later date.
TAG is the action of a fielder in touching a base with the body while holding the ball securely and firmly in the hand or glove; or touching a runner with the ball or with the hand or glove holding the ball, while holding the ball securely and firmly in the hand or glove. It is not a tag, however, if simultaneously or immediately following his touching a base or touching a runner, the fielder drops the ball. In establishing the validity of the tag, the fielder shall hold the ball long enough to prove that he has complete control of the ball. If the fielder has made a tag and drops the ball while in the act of making a throw following the tag, the tag shall be adjudged to have been made.
THROW is the act of propelling the ball with the hand and arm to a given objective and is to be distinguished, always, from the pitch.
TIE GAME is a regulation game which is called when each team has the same number of runs.
"TIME" is the announcement by the umpire of a legal interruption of play, during which the ball is dead.
TOUCH To touch a player or umpire is to touch any part of his body, or any uniform or equipment worn by him.
(Touch) Comment: Equipment shall be considered worn by a player or umpire if it is in contact with its intended place on his person.
TRIPLE PLAY is a play by the defense in which three offensive players are put out as a result of continuous action, providing there is no error between putouts.
WILD PITCH is a pitch that is so high, or low, or wide of the plate that it cannot be handled with ordinary effort by the catcher.
WIND-UP POSITION is one of the two legal pitching positions (the other being the set position).