WebBall.com - Baseball Glossary

Our collection of baseball terms

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A B C D E F G H I J K L M N O P R S T U V W X Y

Phrase	Definition
OBP	In scorekeeping (OBP) or (OB%) is On-base Percentage and (OBA) is On-base Percentage Allowed (used on pitching charts)
Obstruction	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. If a fielder is about to receive a thrown ball and if the ball is in flight directly toward and near enough to the fielder so he must occupy his position to receive the ball he may be considered 'in the act of fielding a ball.' It is entirely up to the judgment of the umpire as to whether a fielder is in the act of fielding a ball. After a fielder has made an attempt to field a ball and missed, he can no longer be in the 'act of fielding' the ball. For example - an infielder dives at a ground ball and the ball passes him and he continues to lie on the ground and delays the progress of the runner, he very likely has obstructed the runner
OFA	(OFA) is Outfield Assists in charting fielders
On the screws	When a batter hits the ball hard. Also 'on the button'
One o'clock hitter	A batter who's great during batting practice but unproductive when it counts
OPS	On-base Plus Slugging (OPS) is on of the lesser stats meant to combine OB% with the power numbers of a slugger. Think of it as giving extra credit for international walks or wextra base hits