An inset is something set within something else, like a small picture placed inside a larger one or a map tucked into the corner of another map. When you look at a map of the United States, you might notice a small inset map showing Alaska and Hawaii in the corner, since they're too far away to fit on the main map at the same scale. In a magazine, an inset photo might show a close-up detail within a larger photograph.

The word also describes a physical object fitted into a space, like an inset sink that sits flush with the countertop rather than sitting on top of it, or decorative tiles that form an inset pattern in a floor.

When used as a verb, to inset means to place something within something else in this way. A book designer might inset a smaller image within a larger illustration to show an important detail, or a carpenter might inset a panel into a door.

The key idea is always about something fitting within something else, creating a layered effect where one thing contains another in a deliberate, often decorative or informative way.