\begin{definition}[Definition:Convex Angle]
A '''convex angle''' is an angle that is larger than a zero angle and smaller than a straight angle.
That is, the measurement of a '''convex angle''' is larger than $0 \degrees$ and smaller than $180 \degrees$.
In radians, the measurement of a '''convex angle''' is larger than $0$ and smaller than $\pi$.
\end{definition}