#drain  a gradual depletion; "a drain on resources"
  supertype:  depletion  the act of decreasing something markedly
  subtype:  drawing_off__drawingoff__drawing  act of getting or draining something such as electricity or a liquid from a source: "the drawing of water from the well"
     subtype:  derivation  drawing off water from its main channel as for irrigation
     subtype:  derivation.drawing_off  drawing of fluid or inflammation away from a diseased part of the body
  subtype:  brain_drain__braindrain  depletion or loss of intellectual and technical personnel

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