polo coat Refers to a casual and loose-fitting style of coat, originally made of camel's hair and worn by polo players in between chukkers. Early polo coats were often belted wrap styles, but the cut that became most identified with the term was the style of loosely fitted, double-breasted coats with patch pockets that Brooks Brothers and other retailers began to offer in the United States before World War I. During the late 1920s, it became identified with prep schools and collegiate style, and later passed into the preppy canon. Synonyms: camel's hair coat, wait coat.
(The Fairchild Encyclopedia of Menswear)