Let $G_X = (X, \mathcal{E}_X)$ be a D2696: Digraph.
An D548: Ordered pair $G_E = (E, \mathcal{E}_E)$ is a subdigraph of $G_X$ if and only if

(1)	$E \subseteq X$	(D78: Subset)
(2)	$\mathcal{E}_E \subseteq \mathcal{E}_X$	(D78: Subset)