Definition of "ullage" [ul•lage]

• The amount of liquid within a container that is lost, as by leakage, during shipment or storage. (noun)
• The amount by which a container, such as a bottle, cask, or tank, falls short of being full. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "NASA said the word "ullage" comes from the French term "ouillage," used in winemaking to describe the space between wine and the top of a storage container."
• "The word "ullage" is taken from the French term "ouillage," which is used in winemaking to describe the space between wine and the top of a storage container, such as a barrel or bottle."
• "NASA said the word "ullage" comes from the French term "ouillage," used in winemaking to describe the space between wine and the top of a storage container. In this case, it refers to the space at the top of the first stage fuel tank and the need to push the fuel to the bottom of the tank. "