quadrature Copy link Outline I. The process of squaring. quadrātūraII. In astron., the being distant 90°. quadrātum • quadrature: I. The process of squaring. quadrātūra: esp. the q. of the circle, circuli q., Apul. Dogm. Plat. 3, p. 37. II. In astron., the being distant 90°. quadrātum: they call these (positions) quadratures, ea quadrata nominant, Cic. Div. 2, 42, 89 esp. the phr. in q. with: the moon is halved when in q. with the sun: luna in quadrato solis dividua est, Plin. 2, 18, 16.