What is the name of a line that intersects two or more coplanar lines at different points?

A line that intersects two or more coplanar lines at different points is specifically called a transversal. This term is used in geometry to describe the unique relationship between the lines it intersects. When a transversal crosses at different points, it creates various angles such as corresponding angles, alternate interior angles, and consecutive interior angles, which are significant in the study of angle relationships and parallel lines.

Understanding this concept is crucial when working with properties of angles formed by parallel lines and transversals, which are foundational topics in geometry. The other terms listed have different meanings: a secant is usually related to a line that intersects a curve at two points, a chord refers to a segment whose endpoints lie on a circle, and a diameter is a specific type of chord that passes through the center of a circle. Thus, the term transversal distinctly identifies the intersecting line with respect to multiple coplanar lines.