A "stay-at-home son" typically refers to an adult man who lives with his parents instead of living independently. Traditionally, the term has been used somewhat pejoratively to describe a man who is unemployed or lacks motivation to get a job or pursue education. However, more recently, some young men have embraced or rebranded the term with a sense of pride or as a lifestyle choice, especially among those who live in affluent families that support them financially. For example, some "stay-at-home sons" may be saving money by living rent-free while attending school part-time, helping their families' businesses, or simply enjoying the benefits of living with their parents without the financial pressures of living alone. They may counter conventional ideas of independence by framing this arrangement as a deliberate and even aspirational lifestyle. This phenomenon is part of a broader trend where more young adults live with their parents due to economic factors like high living costs and limited job opportunities. Some see it as a pragmatic or preferred option rather than a failure to launch.

In short, a stay-at-home son is an adult male who lives at home with his parents, often balancing various personal or economic reasons for doing so, ranging from unemployment and saving money to making a lifestyle statement.