Na-adjective, Noun
1. vacuum; hollow; empty
Wikipedia definition
2. VacuumVacuum is space that is empty of matter. The word stems from the Latin adjective vacuus for "empty". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space.
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