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.
Pater familias
Women emancipated from the "potestas" of a "pater familias" were independent by law ("sui iuris") but had a male guardian appointed to them. A woman "sui iuris" had the right to take legal action on her own behalf but not to administer legal matters for others.