Definition of vacuum in English:

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Pronunciation: /ˈvakˌyo͞o(ə)m/

noun (plural vacuums or vacua /-yo͞oə/)

1A space entirely devoid of matter.
Example sentences
  • Since by definition it contains no matter, the vacuum of space itself has NO temperature.
  • They operate like any rocket engine in the vacuum of space, by propelling gases in one direction to create an opposite and equal force on the craft.
  • I am curious as to exactly when scientists found out that space is a vacuum and not made up of ether?
emptiness, void, nothingness, vacancy, absence, black hole
1.1A space or container from which the air has been completely or partly removed.
Example sentences
  • The chamber was then put into a vacuum overnight to remove any remaining trace of organic solvent.
  • After venting to release the vacuum, he removed the detector flange.
  • He creates a vacuum in a glass container, and places one atom of carbon into it.
1.2 [usually in singular] A gap left by the loss, death, or departure of someone or something formerly playing a significant part in a situation or activity: the political vacuum left by the death of the Emperor
More example sentences
  • The vacuum created by their departure was filled by the club's most committed supporters, who set about raising money and bringing the club back from the brink.
  • The vacuum created by his death 24 years back still remains unfilled.
  • In rural Scotland the retiral of a sitting MP always creates a vacuum which other political parties rush to fill.
gap, space, lacuna, void
2 (plural vacuums) A vacuum cleaner.
Example sentences
  • It would be another ten years before the electric vacuum, iron, and frying pan became available as consumer products.
  • Distractions such as rattles, music, or even running a vacuum, washing machine, or blow-dryer may be amusing or comforting to your baby.
  • This is a combination stick and handheld (dust buster style) vacuum and is proving to be perfect for my small apartment.
vacuum cleaner, vac
trademark Dustbuster, Hoover


[with object]
Clean with a vacuum cleaner: the room needs to be vacuumed
More example sentences
  • I was sick of being the only one who vacuumed common areas, cleaned the bath and toilet or did a load of dishes without quibbling whether I'd eaten off them.
  • Kids don't care if the room has been vacuumed and cleaned.
  • Apparently while I've been at work my son has cleaned up the house, even vacuuming it!


in a vacuum

(Of an activity or a problem to be considered) isolated from the context normal to it and in which it can best be understood or assessed.
Example sentences
  • We cannot exist in a vacuum, in isolation from what's happening in other parts of the world.
  • All this artistic and scientific activity did not, of course, take place in a vacuum.
  • While the film may be primarily an artistic statement, it does not exist like so much art, in a vacuum, but is placed firmly in context.


Mid 16th century: modern Latin, neuter of Latin vacuus 'empty'.

  • This modern Latin word is from Latin vacuus ‘empty’, a base shared by mid 17th-century vacuous meaning, in early examples, ‘empty of matter’. ‘Unintelligent’ became one of the word's meanings in the mid 19th century.

For editors and proofreaders

Syllabification: vac·u·um

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