Final answer:
Fictive kinship refers to the inclusion of non-biologically related individuals as family members through social and emotional ties, as exemplified by referring to a close family friend as 'Aunt' or 'Uncle'.
Step-by-step explanation:
The practice you're referring to is called fictive kinship. It is a social construct where people who are not related by blood or marriage are included in the family group due to strong emotional bonds, feelings of affection, or other significant relationships. This practice is common across various cultures and societies and includes assigning family terms such as 'aunt,' 'uncle,' 'brother,' or 'sister' to these individuals.
In terms of kinship terminology, these would be considered 'terms of address' because they are used to speak directly to the individuals, while 'terms of reference' describe the relationship between individuals. The idea of a 'nuclear family' consisting of parents and their children residing in one household is contrasted with an 'extended family,' which can include a wider array of relatives and even non-related individuals deemed important or close to the family.
Through cultural traditions and norms, families extend beyond mere biology, reflecting the social environment and the emotional roles individuals fulfill within a specific cultural context. This practice is not limited by biological or marital connections and is broadly recognized across different cultures.