cohabit

To cohabit means to live together, usually in the same home. In many modern cases, people think of a couple sharing a house without being married. But it can also describe anyone or any group sharing one place. Imagine two friends sharing an apartment or two pets living in the same home. In history and law, cohabitation has often described people who live together in a close, domestic relationship without formal marriage.

Imagine two birds building a nest together, sharing resources and raising their young. That's a simple example of cohabitation—living side by side. In modern English, however, the word is often linked to human relationships. To cohabit means to live together in a romantic relationship without being married. It usually involves sharing a home, daily routines, and sometimes finances, which many people call a domestic partnership.

However, cohabiting isn't always about romance! The term originally meant "to inhabit together," and it can be used more broadly. You might say that different families cohabit in one shared house, or that certain species of fish cohabit in the same coral reef.

The rise of cohabitation as a common relationship choice reflects changing social rules. For many people, it is a step before marriage, a way to learn how life works together. For others, it is a long-term arrangement they choose because they want flexibility without legal marriage. In many countries, cohabitation also has legal effects around property rights and inheritance. So, whether it is a couple sharing a kitchen, neighbors sharing a house, or animals sharing an ecosystem, "cohabit" points to people or creatures living together in one place and sharing life side by side.