frostback
n.— «Have a feature in today’s Toronto Star on all the “frostbacks” on the January press tour.… Frostbacks is an expression I’d never heard of until Star TV columnist Rob Salem spelled it out for me last July—Canadians working on U.S. network television. It is an expanding list, especially this winter, with a mix of familiar faces and a couple of promising rookies.» —“Lie to Me, Damned Lies and Statistics” by Bill Brioux Bill Brioux’s TV Feeds My Family (Canada) Jan. 20, 2009. (source: Double-Tongued Dictionary)
I first heard this term in the early 70’s. It was used in the National Lampoon Magazine occasionaly in the sense of illeagal immigrants from Canada.