|sociol, anthropol Compare extended family a primary social unit consisting of parents and their offspring|
nuclear family n.
A family unit consisting of a mother and father and their progeny.
A type of family made up only of parents and their children. (Compare extended family.)
in sociology and anthropology, a group of people who are united by ties of partnership and parenthood and consisting of a pair of adults and their socially recognized children. Typically, but not always, the adults in a nuclear family are married. Although such couples are most often a man and a woman, the definition of the nuclear family has expanded with the advent of same-sex marriage. Children in a nuclear family may be the couple's biological or adopted offspring.
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