Definition 106.6.3. Let $\mathcal{X}$ be a locally Noetherian algebraic stack. Let $x \in |\mathcal{X}|$ be a finite type point. The dimension of the local ring of $\mathcal{X}$ at $x$ is $d \in \mathbf{Z}$ if the equivalent conditions of Lemma 106.6.2 are satisfied.

In your comment you can use Markdown and LaTeX style mathematics (enclose it like $\pi$). A preview option is available if you wish to see how it works out (just click on the eye in the toolbar).