Definition 5.8.1. Let $X$ be a topological space.

We say $X$ is

*irreducible*, if $X$ is not empty, and whenever $X = Z_1 \cup Z_2$ with $Z_ i$ closed, we have $X = Z_1$ or $X = Z_2$.We say $Z \subset X$ is an

*irreducible component*of $X$ if $Z$ is a maximal irreducible subset of $X$.

## Comments (2)

Comment #8722 by Roy Shtoyerman on

Comment #9353 by Stacks project on

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