Definition from Wiktionary, the free dictionary
bluecoat (plural bluecoats)
- (UK) A traditional dress code at certain prestigious British schools
- This was a bluecoat school in my day.
- (US history) A soldier or officer in the Union army during the American Civil War
2009 January 18, Ralph Blumenthal, “Re-enactor Is Indicted in Shooting of a Yankee”:
- The shot wounded Thomas Lord, a 73-year-old former New York City police officer from Suffolk, Va., and a bluecoat with the Seventh New York Volunteer Cavalry.
- (dated) A policeman
soldier in the Union army