ullage
ullage (ul"laj; 48) , noun
[Old French eullage, ouillage, the filling up of a cask, from ouillier, oillier, euillier, to fill a wine cask; properly, to add oil to prevent evaporation, as to a flask that is nearly full, from Old French oile oil. See Oil.]
(Commerce) The amount which a vessel, as a cask, of liquor lacks of being full; wantage; deficiency.