noun
set position
Baseball term: the pitcher's stance with the pivot foot on the rubber and the free foot in front, used when runners are on base.
ランナーが出ると、ピッチャーはセットポジションから投げる。
When there are runners on base, the pitcher throws from the set position.
Variant with interpunct, sometimes used for clarity.
Windup position, used with no runners on base; the pitcher starts with a full motion.
Borrowed from English 'set position', a baseball term.