Wiktionary
n. The artistic entertainment and material artifacts associated with a society's aristocracy or most learned members, usually requiring significant education to be appreciated or highly skilled labor to be produced.
Wikipedia
"High culture" is a term now used in a number of different ways in academic discourse, whose most common meaning is the set of cultural products, mainly in the arts, held in the highest esteem by a culture.
In more popular terms, it is the culture of an upper class such as an aristocracy or an intelligentsia, but it can also be defined as a repository of a broad cultural knowledge, a way of transcending the class system. It is contrasted with the low culture or popular culture of, variously, the less well-educated, barbarians, Philistines, or the masses. Both high culture and folk culture act as the repository of shared and accumulated traditions functioning as a living continuum between the past and present.