OS X Mavericks: Remove a backed-up item from your backup disk
From inside the Time Machine starfield, you can delete all copies of a backed-up file or folder from your Time Machine backup disk.
- Open the Time Machine menu in the menu bar, then choose Enter Time Machine.
- Use the arrows or the timeline along the right side of your screen to browse through the backups Time Machine created.
- When you find the item you want to delete, select it, then open the Action menu (looks like a gear) and choose Delete All Backups for the item.
You can move, copy, or delete the Backups.backupdb folder on your Time Machine backup disk as you would other folders. You can also delete folders within the Backups.backupdb folder. You can’t delete individual items inside the dated folders.