Final answer:
A person referred to as 'uncle' despite there being no blood or marriage connection is an example of fictive kinship, a concept where emotional or social ties establish family connections.
Step-by-step explanation:
When a person is called an 'uncle' but he is neither an affinal nor consanguineal relative, this situation describes a fictive kinship. Fictive kinship is a social construct where individuals are regarded as family members, not through blood relation or marriage, but rather through personal choice and the presence of significant emotional or social ties. This kind of kinship is recognized in various societies and is used to solidify community bonds, offer support, and create a sense of extended family beyond biological means.