The common end point of the sides (or arms) of an angle is the vertex of the angle.
The common end point of the sides of an angle is called the vertex. The sides are referred to as rays.
vertex
vertex
vertex
That's the angle's "vertex".
A vertex (plural = vertices).
the vertex is the common endpoint
< the point where the two rays meet is called a vertex.
an angle
Straight Angle
The rays are called sides and the common endpoint is called vertex.