Esoteric refers to knowledge or ideas that are not widely known and are understood or appreciated by only a small number of people, especially those with special knowledge or interest. The term comes from the Greek word esÅterikos meaning "inner" or "further inside". Esoteric knowledge is private, obscure, and exclusive and might be related to subjects such as mysticism or the arcane. In contrast, exoteric knowledge is widespread, accessible, and shared among the general public. The term "esoteric" can also imply that something is hard to understand or has an air of secrecy around it.