'Clearance' definitions:

Definition of 'clearance'

From: WordNet
noun
The distance by which one thing clears another; the space between them
noun
Vertical space available to allow easy passage under something [syn: headroom, headway, clearance]
noun
Permission to proceed; "the plane was given clearance to land"

Definition of 'Clearance'

From: GCIDE
  • Clearance \Clear"ance\ (kl[=e]r"ans), n.
  • 1. The act of clearing; as, to make a thorough clearance. [1913 Webster]
  • 2. A certificate that a ship or vessel has been cleared at the customhouse; permission to sail. [1913 Webster]
  • Every ship was subject to seizure for want of stamped clearances. --Durke [1913 Webster]
  • 3. Clear or net profit. --Trollope. [1913 Webster]
  • 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 cogwheel tooth and the bottom of a space between teeth of a wheel with which it engages. [1913 Webster]
  • Clearance space (Steam engine), the space inclosed in one end of the cylinder, between the valve or valves and the piston, at the beginning of a stroke; waste room. It includes the space caused by the piston's clearance and the space in ports, passageways, etc. Its volume is often expressed as a certain proportion of the volume swept by the piston in a single stroke. [1913 Webster]

Synonyms of 'clearance'

From: Moby Thesaurus