Definition of "quarter-turn" []

• The are subtending an angle of 90°; a bend or change of direction at right angles. (noun)

The Century Dictionary (Public Domain)

• "Gently stretch the surface of the dough around to the bottom on all four sides, rotating the ball a quarter-turn as you go."
• "He did turn his head about a quarter-turn to the right in a lame and transparent attempt to shield his shameful behavior from view."
• "Mr. Adams taught Mr. Lee the same grip and release of the cut fastball that Mr. Fisher had taught him: Hold the baseball off-center, rotate your wrist a quarter-turn in, and throw it with the same motion and force as you would a fastball."