Ox-er

I never knew but apparently the form abbreviation + -er suffix, as in rugger (rugby), soccer (Association Football) and various nicknames (Aggers, Tuffers, etc) has its origins in Oxford. Indeed, apparently Jesus College is known as Jaggers - although I'm not so sure about that myself. If it's not something I've heard in actual speech then I'm sceptical that it's really used (like minus one-th week).