Definition - What does Tenure mean?
Tenure is the legal right to possess something, typically something that is coveted and/or that is valuable.
Tenure can refer to land or property ownership, the ownership of a political position, the holding of a coveted status for a teacher or educator, and a number of other things.
Justipedia explains Tenure
If a teacher has "tenure," this typically means that he or she has earned special privileges after demonstrating his or her worth over a number of years. Teachers who have tenure typically can only be fired if they do certain things. They also usually have priority for certain roles and positions over teachers who do not have tenure.