What is "four-seam fastball"

n. (context baseball English) A backspin pitch thrown with a ball gripped in the direction to cause four of the seams of the ball to cross the flight path and released with roughly equal pressure by the index and middle fingers

thumb|upright=1.75|During a pregame bullpen warmup, Chris Young throws a straight-overhead four-seam fastball.

A four-seam fastball, also called a rising fastball, a four-seamer, or a cross-seam fastball, is a pitch in baseball. It is a member of the fastball family of pitches and is usually the hardest (i.e., fastest) ball thrown by a pitcher. A few pitchers at the major league level can sometimes reach a pitch speed of up to 100 mph. Compare with the two-seam fastball.