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noun di·men·sion \də-ˈmen(t)-shən also dī-\

Simple Definition of dimension

  • : the length, width, height, or depth of something : a measurement in one direction (such as the distance from the ceiling to the floor in a room)

  • : the amount or number of things that something affects or influences

  • : a part of something

Source: Merriam-Webster's Learner's Dictionary

Full Definition of dimension

  1. 1 a (1) :  measure in one direction; specifically :  one of three coordinates determining a position in space or four coordinates determining a position in space and time (2) :  one of a group of properties whose number is necessary and sufficient to determine uniquely each element of a system of usually mathematical entities (as an aggregate of points in real or abstract space) <the surface of a sphere has two dimensions>; also :  a parameter or coordinate variable assigned to such a property <the three dimensions of momentum> (3) :  the number of elements in a basis of a vector space b :  the quality of spatial extension :  magnitude, size c :  a lifelike or realistic quality d :  the range over which or the degree to which something extends :  scope —usually used in plural e :  one of the elements or factors making up a complete personality or entity :  aspect

  2. 2 obsolete :  bodily form or proportions

  3. 3 :  any of the fundamental units (as of mass, length, or time) on which a derived unit is based; also :  the power of such a unit

  4. 4 :  wood or stone cut to pieces of specified size

  5. 5 :  a level of existence or consciousness

dimensional play \-ˈmench-nəl, -ˈmen(t)-shə-nəl\ adjective
dimensionality play \-ˌmen(t)-shə-ˈna-lə-tē\ noun
dimensionally play \-ˈmench-nə-lē, -ˈmen(t)-shə-nəl-ē\ adverb
dimensionless play \-ˈmen(t)-shən-ləs\ adjective

Examples of dimension in a sentence

  1. She carefully measured each dimension of the room.

  2. The social dimensions of the problem must also be taken into account.

Origin of dimension

Middle English, from Anglo-French, from Latin dimension-, dimensio, from dimetiri to measure out, from dis- + metiri to measure — more at measure

First Known Use: 14th century

Other Mathematics and Statistics Terms



verb, di·men·sion

Definition of dimension

dimensioneddimensioning play \-ˈmen(t)-shə-niŋ\

  1. transitive verb
  2. 1 :  to form to the required dimensions

  3. 2 :  to indicate the dimensions of (as on a drawing)


First Known Use of dimension


Rhymes with dimension

DIMENSION Defined for Kids


noun di·men·sion \də-ˈmen-shən\

Definition of dimension for Students

  1. :  the length, width, or height of something

Medical Dictionary


play play
noun di·men·sion \də-ˈmen-chən also dī-\

Medical Definition of dimension

  1. :  measure in one direction; specifically :  one of three or four coordinates determining a position in space or space and time

Seen and Heard

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tending to dismiss important matters

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