This is the process of sending an e-mail then immediately going into sent mail and doing a SHIFT-DELETE to remove the e-mail without going throught the deleted items folder. This is an appropriate tactic when sending sexually explicit e-mails that you don't want recorded by anyone.

Literally everyone, ever. Including the writer of this definition.

1) to permanently delete file(s) on a Windows-based computer.

2) A euphemism for the curse word "shit"