A charity school at which pupils wear blue coats; specifically. Christ's Hospital, originally situated in Newgate, London, now in Horsham, West Sussex; (later more generally) any charity school; now also in the names of conventional schools, some of which were originally charity schools.
Christ's Hospital was established for the education of the poor in 1552. It is well known for its distinctive uniform of blue coats fastened at the waist with a belt, worn with bright yellow stockings. Many similar schools followed Christ's Hospital, often replicating its uniform. Most such schools have now abandoned the blue coats, but these are retained by Christ's Hospital.
Early 18th century.