Prudish in the context of "Hip (slang)"

Hip is a slang for fashionably current and in the know. To be hip is to have "an attitude, a stance" in opposition to the "unfree world", or to what is square or prude. Being hip is also about being informed about the latest ideas, styles, and developments.

Hip, like cool, does not refer to one specific quality. What is considered hip is continuously changing.