clearance Meaning, Definition & Usage

  1. noun the distance by which one thing clears another; the space between them
  2. noun vertical space available to allow easy passage under something
    headroom; headway.
  3. noun permission to proceed
    • the plane was given clearance to land

WordNet

Clear"ance noun
Definitions
  1. The act of clearing; as, to make a through clearance.
  2. A certificate that a ship or vessel has been cleared at the customhouse; permission to sail.
    Every ship was subject to seizure for want of stamped clearances. Durke
  3. Clear or net profit. Trollope.
  4. (Mach.) 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 cogwell tooth and the bottom of a space between teeth of a wheel with which it engages.

Webster 1913