Clearance | Mean of clearance in English Dictionary

/ˈklirəns/

• Noun
• an official decision saying that someone has permission to do something
1. You'll have to get clearance [=approval] from management to go ahead with the project.
2. The documents are only available to people with security clearance [=special permission given only to people who are approved to know or see secret things] from the government.
3. She has a security clearance that allows her to see the classified information.
• official permission for an aircraft, pilot, etc., to do something
1. The pilot got clearance to land.
2. That flight has not received clearance for landing/takeoff.
3. a clearance for landing/takeoff
• the amount of space between two things
1. There was only 10 inches of clearance between the car and the side of the tunnel.
2. The car has a road/ground clearance of seven inches. [=the bottom of the car is seven inches above the road/ground]
3. a bridge with a 100-foot clearance above the water

• the act or process of removing things (such as trees or old buildings) from an area
1. the clearance of forests for farming
2. slum clearance to make room for new housing