curveball, n.All

A Curveball is a slithering fastball

A curveball is able to break up to 17 inches

A Curveball is about having the courage to stay in the box.

A Curveball is a fastball with a curve on it." Classic Yogi

A Curveball is a pitch that appears to be flying straight at your head only to then smack into the catcher's mitt in the strike zone