OS X: Delete single folder of Time Machine Backup via Terminal

sudo /System/Library/Extensions/TMSafetyNet.kext/Helpers/bypass rm -r /Volumes/*/Backups.backupdb/*/*/*/Volumes/One

In 10.7 and earlier bypass was in /System/Library/Extensions/TMSafetyNet.kext/Contents/MacOS/bypass.

Other related questions:

• How can I delete Time Machine files using the commandline
• Can I simply manually delete individual Time Machine backups from the Finder or command line?

Time Machine backups are protected at the kernel level by the TMSafetyNet.kext extension. You'll need to run the bypass utility that is part of that extension's bundle to delete the backed up file. See the answer to this related question on AskDifferent.com for complete details on where to find the bypass utility and how to use it.

How can I delete a file marked as backup item?