What is the definition of a secant in relation to a circle?

A secant is defined as a line that intersects a circle at two distinct points. This definition highlights its key characteristic: while a chord is bounded by the two points it connects, a secant extends infinitely in both directions beyond those points on the circle. This differentiates it from other line types related to circles. For instance, a tangent line touches the circle at only one point and does not cross into the interior of the circle, while a diameter—a specific type of chord—must pass through the center of the circle but does not qualify as a secant since it connects only two points within the circle's boundary. Thus, recognizing that a secant specifically intersects the circle in two places is crucial for understanding its geometric properties and significance.