Green’s Dictionary of Slang

(US) one who attends one of the major US ‘prep’ schools (St Paul’s, Choate, Groton, Miss Porter’s, Dana Hall etc), the equivalent of the UK’s public (i.e. fee-paying, private) schools. The graduates of such schools are the children of the US establishment and share similar codes, styles, language and society; can be used of men and women, although prepette is specifically female.

1956		Harvard Crimson 29 Mar. 🌐 Eliot [House at Harvard] is crawling with preppies.
1967–8		Baker et al. CUSS 176: Prep A socially adept person. A well-dressed person, male [...] female. Preppy A well-dressed person, male.
1970		Harper’s Mag. Oct. 103: No longer believe that Harvard students are all rich preppies.
1981		Eble Campus Sl. Mar. 5: prepette – a female attired in the popular prep fashion [...] Usually derogatory.
1985		Totally True Diaries of an Eighties Roller Queen 🌐 1 Mar. When they played metal at the Roundabout all the preps sat on the floor. The metalers got mad.
1986		C. Hiaasen Tourist Season (1987) 224: They walked out that way, right past the Old Spice preppies.
1995		J. Stahl Permanent Midnight 316: A swarthy prepster in tennis shoes.
1998		C. Fleming High Concept 131: An East Coast preppie who has come west and found employment.
1999		Blackboiz for Other Boiz 🌐 16 May I like preps, jocks, punks, skins, whatever your declaration as long as you know what’s going on.
1999		K. Sampson Powder 286: Tom left them with Rudy Wexner, a pink-cheeked preppy.
2002		(con. 1980s) i80s.com 🌐 preppie/preppy A collegiate type, someone who wore Polo or Izod shirts, deck shoes and a cloth belt. Preppies usually grew up to be yuppies.
2012		T. Robinson ‘Last Call’ in Dirty Words [ebook] ‘Preppy-looking fella’.
2021		S.A. Crosby Razorblade Tears 103: This preppy-looking son of a bitch.