Permanent means lasting forever or for a very long time without changing. When something is permanent, it stays put and doesn't go away easily.

A permanent marker is called permanent because it creates marks that won't wash off like pencil or washable markers do. Your permanent teeth are the adult teeth that replace your baby teeth: they're meant to last for the rest of your life. A permanent resident of a country has official permission to live there indefinitely, not just visit temporarily.

The opposite of permanent is temporary. A temporary tattoo washes off after a few days, but a permanent tattoo is meant to stay on your skin for life. A substitute teacher is temporary, but your regular classroom teacher has a permanent position at the school.

Sometimes people use “permanent” more casually to mean “a really long time” rather than literally forever. When someone says that stain looks permanent, they might mean it's very difficult to remove, not that it will actually last until the end of time. But usually, permanent suggests something meant to endure, like a permanent scar, a permanent home, or a permanent change to how something works.