Let $T = (X, \mathcal{T})$ be a D1106: Topological space such that

(i)	$\mathcal{T}_{\text{closed}}$ is the D2439: Set of closed sets in $T$

The closure of $E \subseteq X$ in $T$ is the D11: Set \begin{equation} \text{cl}_T E : = \bigcap \{ F : E \subseteq F \in \mathcal{T}_{\text{closed}} \} \end{equation}