In baseball, a sacrifice fly (sometimes abbreviated to sac fly) is defined by Rule 9.08(d):[1] "Score a sacrifice fly when, before two are out, the batter hits a ball in flight handled by an outfielder or an infielder running in the outfield in fair or foul territory that
They are so named because the batter allows a teammate to score a run, while "sacrificing" his or her ability to do so. They are traditionally recorded in box scores with the designation "SF".