\begin{definition}[Definition:Orthic Triangle]
Let $\triangle ABC$ be a triangle.
Let $\triangle DEF$ be the triangle formed by the feet of the altitudes $AD$, $BC$ and $ED$ of $\triangle ABC$.
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$\triangle DEF$ is known as the '''orthic triangle of $\triangle ABC$'''.
That is, the '''orthic triangle of $\triangle ABC$''' is the pedal triangle of its orthocenter.
\end{definition}