Deploying Reusable Workflow means that it becomes available as a SharePoint workflow.

When you created Reusable Workflow (to create Reusable workflow click here) go to List settings -> Workflow settings and associate your reusable workflow for the selected content type.

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Notice: To have access to all workflows associated with content types, you have to enable management of content types in the list’s Advanced Settings.

When the new Reusable Workflow’s definition is deployed, then it can be used as a regular SharePoint reusable workflow (like applying it to lists and content types with available SharePoint tools).

Go to your list and click "Workflows" on selected item.

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