Preppy is a description of a person who behaves or dresses in a manner reminiscent of a student at a "preparatory school" (a private middle school or high school).

Typically, this would be a member of the upper or upper middle class who dresses in Polo, Izod, or Ralph Lauren clothing, often with their shirt collar turned upwards, or a sweater tied around their neck.

The name is similar in formation to hippie or yuppie, and had greater currency in the 1970s and 1980s.