Definition 77.16.2. Let $B \to S$ as in Section 77.3. Let $(U, R, s, t, c)$ be a groupoid in algebraic spaces over $B$. The group algebraic space $j^{-1}(\Delta _{U/B}) \to U$ is called the stabilizer of the groupoid in algebraic spaces $(U, R, s, t, c)$.

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