Sui generis
A similar case that led to the use of the label "sui generis" is the relationship of New Caledonia relative to France, because the legal status of New Caledonia can aptly be said to lie somewhere between a French overseas collectivity and a sovereign nation. Although other examples of such status for other dependent or disputed territories may exist, this arrangement is unique within the French realm.
Eugenics
Eugenics (; from Greek εὐγενής "eugenes" 'well-born' from εὖ "eu", 'good, well' and γένος "genos", 'race, stock, kin') is a set of beliefs and practices that aims at improving the genetic quality of a human population by excluding (through a variety of morally criticized means) certain genetic groups judged to be less desirable and promoting other genetic groups judged to be superior. The exact definition of "eugenics" has been a matter of debate since the term was coined by Francis Galton in 1883. The concept predates this coinage, with Plato suggesting applying the principles of selective breeding to humans around 400 BCE.