Measurement or measure of a complex number?

Question

In math, do we write "measure of an angle of two vectors" or "measurement of an angle of two vectors"?

Answer 1

The correct way to say that is "measure of the angle between two vectors", note that "the" is important since it isn't an arbitrary angle between the two vectors, we consider the convex angle ($0\leq\theta\leq\pi)$, so it is only one. Measurement sounds more like a physical thing in my opinion, so measure fits better in here.