v.1. To be launched off the ground. Used of rockets: The astronauts were strapped in their seats and ready to blast off.
2. To launch some rocket from the ground: The space agency needs a new location to blast off its spacecraft. The kids set up their model rockets on the field and blasted them off.
3. To explode or fire something: I blasted off some firecrackers during the celebration. I put some bullets in the gun and blasted a few rounds off to test it.
4. To dislodge or remove something with an explosion: Be careful not to blast your fingers off with that loaded gun! To make room for the new road, the workers blasted off a large rock from the side of the hill.
5. Slang To depart for a destination: We need to blast off right now if we are going to get to the party on time.