clearance >> /ˈklɪrəns/
Definition: [noun] The action or process of removing or getting rid of something or of something's dispersing.
Example: cleaning of the machine should include clearance of blockages
Definition: [noun] Official authorization for something to proceed or take place.
Example: getting diplomatic clearance to fly into or over a country is not always easy
Definition: [noun] Clear space allowed for a thing to move past or under another.
Example: always give cyclists plenty of clearance