"Jock" is an interesting one because it can be used as both an insult and as a respectful reference when talking about a Scottish person. Derived from the Scots language nickname for "John" - which is "Jack" in English - "jock" can be used as an insult, particularly in sporting terms, to refer to Scottish players and supporters. Author Ian Rankin even drew on his own experience of receiving prejudice while living in London when mentioning the terms "Jock" and "Jockland" (Scotland) in his detective novel Tooth & Nail. Interestingly though, a Jock can be a respectful term for the Scottish elite, particularly when referring to the Highland troops - but be careful, it can also be derogatory!