Definition 70.10.1. Let $S$ be a scheme. Let $X$ be an algebraic space over $S$. The sheaf of meromorphic functions on $X$ is the sheaf $\mathcal{K}_ X$ on $X_{\acute{e}tale}$ associated to the presheaf displayed above. A meromorphic function on $X$ is a global section of $\mathcal{K}_ X$.

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