👉 In geometry, a "postcavae" is defined as an element that is perpendicular to both the circle and its tangent line at any given point on the circumference of the circle. This means that it intersects the circle in exactly one point, forming two distinct points on the circumference of the circle. The postcavae are often used in geometry problems involving circles, such as finding the radius or diameter of a circle when the distance from the center of the circle to any point on its circumference