A session is a period of time set aside for a specific activity or purpose. When your class has a math session, that's the chunk of time devoted to working on math. A recording session is when musicians gather in a studio to record their music. A practice session might be when your basketball team works on drills and plays for an hour after school.

The word suggests something more structured and purposeful than just “a while” or “some time.” You don't have a session of watching clouds drift by, but you might have a tutoring session, a gaming session with friends, or a study session before a big test. Each session has a beginning and an end, and usually a goal or focus.

In government, a legislative session is the period when Congress or a state legislature meets to debate and vote on laws. Courts hold sessions when they're officially conducting trials and hearings. Schools are sometimes described as being in session, meaning classes are actively meeting rather than being on break.

The word can also mean a single meeting in a series, such as one therapy session among many, or the third session of a summer camp program. Each session builds on the previous ones toward a larger goal.