Clearance

From Wikipedia, the free encyclopedia

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).
• The distance between two electrical conductors in a gas medium.
• 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 action
  • a security clearance
• in 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
• in Australian rules football, the clearing of the ball out of a stoppage situation, to the advantage of one team or the other