<p><strong>Verb (used with or without object)</strong></p><ul><li>to arch slightly; bend or curve upward in the middle.</li></ul><p><strong>Noun</strong></p><ul><li>a slight arching, upward curve, or convexity, as of the deck of a ship.</li><li>a slightly arching piece of timber.</li><li>Aeronautics. the rise of the curve of an airfoil, usually expressed as the ratio of the rise to the length of the chord of the airfoil.</li><li>Automotive. the outward or inward tilt of a wheel, called positive when the top tilts outward and negative when it tilts inward, measured as the angle, in degrees, between the vertical and a plane through the circumference of the tire.</li></ul>