Definition:Flasque Sheaf of Sets on Topological Space

Definition
Let $X$ be a topological space.

Let $\FF : \map {\mathbf {Ouv} } X^{\mathrm {op} } \to \mathbf {Set}$ be a sheaf of sets on $X$.

$\FF$ is flasque for all open subsets $V \subset U \subset X$, the restriction map $\map{\FF}{U} \to \map{\FF}{V}$ is surjective.