preppy

 
Pronunciation: /ˈprɛpi/
(also preppie)
informal, chiefly US

noun (plural preppies)

  • a pupil or graduate of an expensive prep school, or a person resembling such a pupil in dress or appearance.

adjective (preppier, preppiest)

  • of or typical of a pupil or graduate of an expensive prep school, especially with reference to their neat style of dress: the preppy look

Origin:

early 20th century: from prep school + -y2