Definition 110.33.12. A scheme $X$ is called integral if $X$ is nonempty and for every nonempty affine open $U \subset X$ the ring $\Gamma (U, \mathcal{O}_ X) = \mathcal{O}_ X(U)$ is a domain.

Comment #1068 by Lenny Taelman on

...and X is non-empty, as in 01OK.

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