'''Ullage''' describes the [[space]] not filled with [[liquid]] in a drum, tank or other container.<ref>U.S. Department of Transportation Maritime Administration [http://www.marad.dot.gov/publications/glossary/glossary.html]</ref>
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'''Ullage''' describes the [[space]] not filled with [[liquid]] in a drum, tank or other container.<ref>[http://www.marad.dot.gov/publications/glossary/glossary.html U.S. Department of Transportation Maritime Administration]</ref>