Ullage

(n.) The amount which a vessel, as a cask, of liquor lacks of being full; wantage; deficiency.

Thesaurus Entries

arrear, arrears, back debts, back payments, bouncing check, break, debt, decline, defalcation, default, defect, defectiveness, deferred payments, deficiency, deficit, deficit financing, delinquency, discontinuity, dollar gap, due, failure, falling short, gap, hiatus, imperfection, inadequacy, indebtedness, inferiority, insufficiency, interval, lack, lacuna, liability, missing link, need, obligation, omission, outage, overdraft, short measure, shortage, shortcoming, shortfall, slump, ullage, underage, want, wantage