Definitions for "Kill file"
A list of subjects that you don't want to read about. The news client will not display headers that match criteria in the kill file. For example, if you follow the rec.collecting forum, you might tell your news client to "kill" any header that contains the words "Franklin Mint." Kill files can apply to all subscribed groups or to one specific group.
a list of people whose messages you don't want to read, i.e. their messages just get deleted immediately - also used to ignore topics not of interest to you
a feature of many newsreaders that allows you to block any individual you choose, so that you don't even have to see their posts