Definition of basement in English:

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Pronunciation: /ˈbeɪsm(ə)nt/


1The floor of a building which is partly or entirely below ground level: they went down the stairs into the basement [as modifier]: a basement flat
More example sentences
  • The house is divided horizontally so that she has the basement and ground floor and he has the first and second.
  • Radon levels are generally highest in basements and ground floor rooms that are in contact with the soil.
  • They all have two storeys - either basement and ground, or first floor and attic space.
cellar, vault, crypt, undercroft, underground room, catacomb;
British  lower ground floor;
Scottish  dunny
British dated below stairs
1.1 Geology The oldest formation of rocks underlying a particular area: [as modifier]: basement rocks
More example sentences
  • The best preserved eclogites are found in mafic rocks hosted within the basement sequence.
  • However, basement rocks can also be inferred from exposures in the uplands that surround the basin.
  • The nature of the magnetic basement underlying the east side of the profile is enigmatic.


Mid 18th century: probably from archaic Dutch basement 'foundation', perhaps from Italian basamento 'column base'.

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