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drawdown

[draw-doun]
noun
  1. a lowering of water surface level, as in a well.
  2. a reduction or depletion: a drawdown of weapons in an arms-limitation plan.

Origin of drawdown

1780–90, for literal sense; draw + down1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for drawdown

drawdown

noun
  1. a depletion or reduction, for example of supplies
  2. a continuous decline in an investment or fund, usually expressed as a percentage between its highest and lowest levels
  3. the intentional draining of a body of water such as a lake or reservoir, to a given depth
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for drawdown
n.

of troops, by 1991, in reference to the end of the Cold War; from draw (v.) + down (adv.). Earlier of wells (c.1900).

Online Etymology Dictionary, © 2010 Douglas Harper
drawdown in Science

drawdown

[drô′doun′]
  1. A lowering of the water level in a reservoir or other body of water, especially as the result of withdrawal.
  2. The difference in elevation between the level of water in a well and the level of groundwater in the area in which the well is located.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.