drainage Meaning, Definition & Usage

  1. noun emptying something accomplished by allowing liquid to run out of it
    drain.

WordNet

Drain"age noun
Definitions
  1. A draining; a gradual flowing off of any liquid; also, that which flows out of a drain.
  2. The mode in which the waters of a country pass off by its streams and rivers.
  3. (Engin.) The system of drains and their operation, by which superfluous water is removed from towns, railway beds, mines, and other works.
  4. Area or district drained; as, the drainage of the Po, the Thames, etc. Latham.
  5. (Surg.) The act, process, or means of drawing off the pus or fluids from a wound, abscess, etc.

Webster 1913