What is the term for a segment connecting non-consecutive vertices of a polygon?

The term for a segment connecting non-consecutive vertices of a polygon is indeed a diagonal. In the context of polygons, a diagonal is defined as any line segment that connects two vertices which are not adjacent to each other. For instance, in a pentagon, if you connect vertex A to vertex C, that segment is a diagonal since A and C are not consecutive vertices.

In contrast, an edge refers to the line segment that connects two consecutive vertices in the polygon. A face typically applies to three-dimensional shapes, representing one of the flat surfaces on the shape. Lastly, a chord applies specifically to circles rather than polygons and connects two points on the circumference of a circle. Hence, the choice of diagonal is accurate as it specifically describes the connection of non-adjacent vertices within the context of polygons.