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acre-inch

[ey-ker-inch]
noun
  1. one-twelfth of an acre-foot, equal to 3630 cubic feet.

Origin of acre-inch

An Americanism dating back to 1905–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for acre-inch

acre-inch

noun
  1. the volume of water that would cover an area of 1 acre to a depth of 1 inch; one twelfth of an acre-foot: equivalent to 3630 cubic feet or 102.8 cubic metres
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