Definition - What does Cancelbot mean?
A cancelbot is a tool for the bulletin-board Usenet Internet groups that effectively cancels a message or post. Administrators or others send cancelbots to automatically erase duplicate material, objectionable material or other unwanted content.
Techopedia explains Cancelbot
Developed in the 1980s, Usenet was an early form of Internet forum built on a command line, text-only interface. Cancelbots are a utility of this platform, and have been debated as potentially censorious or stifling to free expression in Usenet groups.
In fact, the use of cancelbots cuts both ways. For instance, a cancelbot released in September of 1996 was said to have "wiped out" 25,000 messages in a somewhat arbitrary way. Other instances of cancelbots appear to have been generated for a single user's preferences. However, systems administrators like to have the ability to cull listings with cancelbots in particular ways.