Yes, you can delete any sprint, if you have needed rights. Deleting a Sprint will remove it from the Project sprints list and its association with work items will end. Sprint field of all its associated items will be left empty. To see your Projects Sprint list and delete a sprint

Click on Navigation Menu, Sprint > Manage all sprints > select the sprint and press delete button.

A notification will confirm that selected sprint is deleted. In Backlog, all undone work items of the deleted sprint will be listed now. You can also see the difference in Backlog statistics by clicking on quick filter groups.