vacuum

plural vacuums · error unknown tag formal plural rare vacua · alternative rare vacuüm

1. A region of space that contains no matter.

   1 more example

   The Wards are open-topped, with skyscrapers rising from the superstructure. Towers are sealed against vacuum, as the breathable atmosphere envelope is only maintained to a height of about seven meters. The atmosphere is contained by the centrifugal force of rotation and a "membrane" of dense, colorless sulphur hexafluoride gas, held in place by carefully managed mass effect fields.

   2008, BioWare, Mass Effect (Science Fiction), Redwood City: Electronic Arts, →ISBN, →OCLC, PC, scene: Citadel Station: Wards Codex entry

   Synonyms: vacancy, void · Antonyms: plenum

2. The condition of rarefaction, or reduction of pressure below that of the atmosphere, in a vessel, such as the condenser of a steam engine, which is nearly exhausted of air or steam, etc.

   a vacuum of 26 inches of mercury, or 13 pounds per square inch

3. abbreviationcolloquialellipsisonly pluralized as "vacuums"Ellipsis of vacuum cleaner.

   Synonyms: hoover

4. natural sciencesA spacetime having tensors of zero magnitude.
5. natural sciencesA ground state of a quantum field or of local spacetime, or more abstractly the lowest-energy state of a system.
   1. string theorynatural sciencesA description of spacetime resulting from a particular compactification of spatial dimensions.
6. An emptiness in life created by a loss of a person who was close, or of an occupation.

   Henrietta soon found a terrible vacuum left, by the letters in which she used to pour forth every feeling and thought to her uncle.

   1837, L[etitia] E[lizabeth] L[andon], Ethel Churchill: Or, The Two Brides. […], volume III, London: Henry Colburn, […], →OCLC, pages 82–83

7. An exercise in which one draws their abdomen towards the spine.

   Right I'm off to practice my vacuum - suck in those stomachs now!

   1997 January 6, John, “I'm 14; How do I start bodybuilding?”, in misc.fitness.weights (Usenet)

   3 more examples

   Abs show up in a most-muscular shot, a vacuum shot, the hands-behind-head compulsory ab shot, twisting poses, and so on.

   1985, Arnold Schwarzenegger, Encyclopedia of Modern Bodybuilding, New York, N.Y.: Simon & Schuster, →ISBN, page 508

   When I do the 'gut vacuum' exercise the abdominal wall seems to return to normal size, as far as I can tell under the flab.

   2010 January 7, Silent Stone, “Want to start, have a few questions for now.”, in misc.fitness.weights (Usenet)

   Blessed with round muscle bellies and a phenomenal structure, he also performed a vacuum pose on stage.

   2022 October 10, Aaromal Maanas, “2022 Tsunami Nutrition Pro Results and Recap”, in Sportskeeda, archived from the original on 23 Oct 2022

present singular third person vacuums · participle present vacuuming · participle past vacuumed · past vacuumed · alternative rare vacuüm

1. transitiveTo clean (something) with a vacuum cleaner.

   “Who in the world cleans an attic? That's like vacuuming a shed.”

   2016, Janice M. Whiteaker, Run

   Synonyms: hoover

2. intransitiveTo use a vacuum cleaner.

   Synonyms: to do the hoovering, to hoover

3. transitivecomputingTo optimise a database or database table by physically removing deleted tuples.

   But the advantage of an auto-vacuumed database is that when B-tree pages are no longer needed, they are moved to the end of the database file and then the database file is truncated, thus returning the unused pages back to the filesystem.

   2010, Ivan Litovski, Richard Maynard, Inside Symbian SQL: A Mobile Developer's Guide to SQLite, John Wiley & Sons, →ISBN, page 337