public school boy
/ˌpʌblɪk ˈskuːl ˌbɔɪ/noun
Chiefly in the sense of public school. A boy who attends a public school; a man who attended a public school as a boy, and who displays the characteristics associated with a public school education.
Origin
Mid 19th century; earliest use found in Catholic World. From public school + boy.