Sui generis
Sui generis ( , ) is a Latin phrase that means "of its/their own kind" or "in a class by itself", therefore "unique". Several disciplines use the term to refer to unique entities. These include: Biology, for species that do not fit into a genus that includes other species Creative arts, for artistic works that go beyond conventional genre boundaries Law, when a special and unique interpretation of a case or authority is necessary Intellectual property rights, for types of works not falling under general copyright law but protected through separate statutes Philosophy, to indicate an idea, an entity, or a reality that cannot be reduced to a lower concept or included in a higher concept Biology In the taxonomical structure "genus → species", a species is described as sui generis if its genus was created to classify it (i.e., its uniqueness at the time of classification merited the creation of a new genus, the sole member of which was initially the sui generis species). A species that is the sole extant member of its genus (e.g., the genus Homo) is not necessarily sui generis; extinctions may have eliminated other congeneric species. A sui generis genus may also be called