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definitions

ullage

[uhl-ij]
noun
  1. the amount by which the contents fall short of filling a container, as a cask or bottle.
  2. the quantity of wine, liquor, or the like, remaining in a container that has lost part of its contents by evaporation, leakage, or use.
  3. Rocketry. the volume of a loaded tank of liquid propellant in excess of the volume of the propellant; the space provided for thermal expansion of the propellant and the accumulation of gases evolved from it.

Origin of ullage

1400–50; late Middle English < Anglo-French ulliage; Old French ouillage, (h)eullage wine needed to fill a cask, equivalent to (a)ouill(er) to fill (a cask) (derivative of ouil eye, hole < Latin oculus) + -age -age
Related formsul·laged, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for ullage

ullage

noun
  1. the volume by which a liquid container falls short of being full
    1. the quantity of liquid lost from a container due to leakage or evaporation
    2. (in customs terminology) the amount of liquid remaining in a container after such loss
verb (tr)
  1. to create ullage in
  2. to determine the amount of ullage in
  3. to fill up ullage in
Derived Formsullaged, adjective

Word Origin for ullage

C15: from Old French ouillage filling of a cask, from ouiller to fill a cask, from ouil eye, from Latin oculus eye
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 ullage
n.

"amount by which a cask or bottle falls short of being full," late 15c., from Anglo-French ulliage (early 14c.), Anglo-Latin oliagium (late 13c.), Old French ouillage, from ouiller "to fill up (a barrel) to the bung," literally "to fill to the eye," from ueil "eye," from Latin oculus (see eye (n.)).

Online Etymology Dictionary, © 2010 Douglas Harper