v.1. To allow someone to disembark from a vehicle: My house is just down the street, but you can let me off at the corner. The bus driver let off the passengers at the terminal.
2. To excuse or pardon someone from something unpleasant, as punishment or work: I'm going to let you off this once, but if I catch you cheating again, you're going to be expelled. The police arrested the leader and let off the rest of the gang with only a warning.
3. To emit something, as heat, gas, or sound: The stove lets off a lot of heat.
4. To detonate or discharge something: The police officer let off a warning shot. We let a firecracker off in the park.