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water-inch

American  
[waw-ter-inch, wot-er-] / ˈwɔ tərˈɪntʃ, ˈwɒt ər- /

noun

Hydraulics.
  1. the quantity of water (approx. 500 cubic feet) discharged in 24 hours through a circular opening of one inch diameter leading from a reservoir in which the water is constantly only high enough to cover the orifice.


Etymology

Origin of water-inch

First recorded in 1850–55