To terminate means to bring something to an end or to stop it completely. When a teacher terminates a class discussion, she brings it to a close. When a company terminates a contract, it officially ends the agreement. When a train reaches its final station, that stop is called the terminus because the route terminates there.

The word suggests a definite, formal ending rather than something that just fades away. A subscription service might terminate your account if you don't pay. A principal might terminate an after-school program that isn't working well. Scientists terminate an experiment when they've collected all the data they need.

In science fiction, the word often describes robots or machines designed to destroy. In everyday conversation, though, terminate usually just means to end something officially or deliberately. When you hear that someone's employment was terminated, it means they were fired or their job ended. The word carries a sense of finality: once something is terminated, it's really over.