Someone who proctors university exams--that is, the person responsible for telling you to put your coats under your chairs who walks around the room sniffing out cheaters. This was a term I'd never heard until I moved from the United States to Canada. My guess is that the administration at McGill uses the term in order to sound as official as possible.
Sounds like an action-figure who's special power is one of impalement. But maybe that's just me.