To circumscribe means to draw a boundary around something or to limit and restrict it. The word comes from Latin roots meaning “to write around.”

In geometry, when you circumscribe a circle around a triangle, you draw the smallest circle that touches all three corners of the triangle. The circle wraps around the triangle perfectly, marking its outer limits.

In everyday life, circumscribe means to set limits or boundaries on what someone can do. A teacher might circumscribe students' free time during a field trip by requiring everyone to stay within the museum's main galleries. Parents might circumscribe their child's screen time to one hour per day. When a law circumscribes people's actions, it defines what they cannot do.

The word suggests careful, deliberate limitation rather than harsh restriction. A coach might circumscribe practice rules to keep players safe, or a scientist might circumscribe the scope of an experiment to focus on specific questions. When something is circumscribed, it operates within defined boundaries, like a dog playing freely but only within a fenced yard.