'ullage' definitions:
Definition of 'ullage'
From: WordNet
noun
The amount that a container (as a wine bottle or tank) lacks of being full
Definition of 'ullage'
From: GCIDE
- ullage \ul"lage\ ([u^]l"l[asl]j; 48), n. [OF. eullage, ouillage, the filling up of a cask, fr. ouillier, oillier, euillier, to fill a wine cask; properly, to add oil to prevent evaporation, as to a flask that is nearly full, fr. OF. oile oil. See Oil.] (Com.) The amount which a vessel, as a cask, of liquor lacks of being full; wantage; deficiency. [1913 Webster]