Stationary can mean:

• Fixed in position, or mode : immobile.
• Unchanging in condition or character.
• In statistics: a stationary process.
• In mathematics: a stationary point.
• In mathematics: a stationary set.
• In physics: a stationary physical process.

The word is sometimes confused with stationery, meaning paper or office supplies. However also see stationary word origin, which shows that "stationary" is the original spelling and is also the most common spelling today.

Stationär