The Collaborative International Dictionary of English v.0.48:
Redcoat \Red"coat`\ (-k[=o]t`), n. One who wears a red coat; specifically, a red-coated British soldier. [1913 Webster]WordNet (r) 3.0 (2006):
redcoat n 1: British soldier; so-called because of his red coat (especially during the American Revolution) [syn: redcoat, lobsterback]