jargon.artrocity.com
New Hacker's Dictionary the Jargon File v 4.4.6
[from the acronym for ‘Terms Of Service’ playing on the verb “toss”]
1. The act of terminating an Internet access account because the owner breached the terms of service (e.g. by spamming).
2. To successfully complain to the ISP for that reason so that they then close the account.