Definition of a Nuclear Family

Nuclear family

The traditional definition of a nuclear family is a family unit that includes two married parents of opposite genders and their biological or adopted children living in the same residence. However, the term "nuclear family" can mean several things in today's society. Understanding the classic roles in this type of family and how it is defined can help you understand the relationships in your own family, whether it's nuclear or not.

History of the Nuclear Family

According to the Merriam-Webster Dictionary, the term "nuclear family" was first used in 1947, but the concept of a family that consists of just parents and children is much older. This basic unit of a family's structure has existed for millennia, but it wasn't until the 1960s and 1970s that the nuclear family became the majority situation. At that time, industrial economic booms and rising wages made it possible for young parents to afford their own homes without living with extended family members. At the same time, better healthcare contributed to the nuclear family, as elderly members became more self-sufficient and independent for decades after their children were grown.

Today, the era of the nuclear family is often glamorized, complete with mom in the kitchen, dad out earning the paychecks, and the kids building a tree house or hosting a stuffed animal tea party. In reality, there is no ideal type of family, and today's definition of a nuclear family can greatly differ from what it was a few decades ago.

Who Is Part of a Nuclear Family

A nuclear family, also called a conjugal, elementary, or traditional family, typically consists of two married or legally bound parents and their biological or adopted children all living in the same residence and sharing the values, duties, and responsibilities of the family unit. There can be any number of children in the family, and one or both parents may work outside the home.

There are pros and cons to the small, nuclear family.


  • Family members develop greater self-sufficiency and independence
  • Family members share the strongest bonds with their immediate relatives
  • Less conflict of family values across different generations


  • Less support emotionally or financially for individual family members
  • Less contact with extended family members may result in lost traditions or poor communication
  • Smaller families may be less resilient in emergencies due to a smaller support structure

Each family adapts according to its size and needs, and just because a family may be defined as nuclear does not mean there are no strong bonds with extended family members. How each family encourages family values and connections varies, and there is no right or wrong family style.

Changing Definition of Nuclear Families

The nuclear family today may be in the minority considering the increasing diversity of Western societies. While the classic definition of a nuclear family may only include two parents of opposite genders, today's definition often includes two-parent families with same-sex parents raising the biological children of one parent or the children that both have adopted. Other types of families, such as single parents, non-married parents, foster families, blended families, and couples without children are on the rise, and the traditional nuclear family, while still strong, is increasingly in the minority.

Definition of a Nuclear Family