CLEARANCE

n. release; cleaning, washing

A clearance can refer to:in engineering and safety, a physical distance or space tolerance, as in a truck (lorry), train or boat under a bridge as well as a train in a tunnel (see structure gauge and loading gauge).a closeout or final sale an authorization or permission from an authority, for example:in aviation, from air traffic control for an aircraft to proceed with a takeoff or landing, or other actiona security clearancein medicine, clearance is the rate at which a substance is removed or cleared from the body by the kidneys and/or in renal dialysis.in finance, the verification of information between the two brokers in a securities transaction
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Noun
1. the distance by which one thing clears another; the space between them
(hypernym) interval, separation
(derivation) clear, top
2. vertical space available to allow easy passage under something
(synonym) headroom, headway
(hypernym) room, way, elbow room
3. permission to proceed; "the plane was given clearance to land"
(hypernym) license, permission, permit
(derivation) authorize, authorise, pass, clear

(n.)
The distance by which one object clears another, as the distance between the piston and cylinder head at the end of a stroke in a steam engine, or the least distance between the point of a cogwheel tooth and the bottom of a space between teeth of a wheel with which it engages.
  

(n.)
The act of clearing; as, to make a thorough clearance.
  

(n.)
Clear or net profit.
  

(n.)
A certificate that a ship or vessel has been cleared at the customhouse; permission to sail.
  

See also Cleared terms.