A derogatory slur usually used to insult Catholics, Irish people or Celtic FC supporters, or some combination of all three, mostly heard in the UK. Ajax Amsterdam supporters also made a banner featuring this term, which resulted in a heavy fine against the club. It is a loose reference to a historical pro-Irish Independance movement notorious for its use of violence.
"Oy, that Fenian Bastard with the Celtic jersey just called me a wanker!"
von Bumboclot 12. November 2013