/ ˈklɪərəns; NAmE ˈklɪr-/ noun
1.
[ C , U ] the removal of things that are not wanted :
forest clearances
slum clearance (= the removal of houses that are in very bad condition in an area of a town)
a clearance sale (= in a shop / store, when goods are sold cheaply to get rid of them quickly)
2.
[ U , C ] the amount of space or distance that is needed between two objects so that they do not touch each other :
There is not much clearance for vehicles passing under this bridge.
a clearance of one metre
3.
[ U , C ] official permission that is given to sb before they can work somewhere, have particular information, or do sth they want to do :
I'm waiting for clearance from headquarters.
All employees at the submarine base require security clearance.
4.
[ U ] official permission for a person or vehicle to enter or leave an airport or a country :
The pilot was waiting for clearance for take-off.
5.
[ U , C ] the process of a cheque being paid by a bank
6.
[ C ] a clearance in football ( soccer ) and some other sports is when a player kicks or hits the ball away from the goal of his or her own team