\begin{definition}[Definition:Centroid/Solid Figure]
Let $F$ be a solid figure.
Let $F$ be divided into a large number $n$ of small elements.
Consider one point of each of these elements.
Let a weight function be associated with this set of points.
Let $G$ be the centroid of each of these weighted points.
Let $n$ increase indefinitely, such that each element of $F$ converges to a point.
Then the limiting position of $G$ is the '''centroid''' of $F$.
\end{definition}