Definition 89.14.4. Let $\mathcal{F}$ be a predeformation category. We say a versal formal object $\xi$ of $\mathcal{F}$ is minimal1 if for any morphism of formal objects $\xi ' \to \xi$ the underlying map on rings is surjective. Sometimes a minimal versal formal object is called miniversal.

[1] This may be nonstandard terminology. Many authors tie this notion in with properties of tangent spaces. We will make the link in Section 89.15.

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