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

Definition of dimension

  1. 1a mathematics (1) :  measure in one direction the dimensions of the room; specifically :  one of three coordinates (see 3coordinate 1a) 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 (such as an aggregate of points in real or abstract space) the surface of a sphere has two dimensions; also :  a parameter (see parameter 1) or coordinate variable assigned to such a property the three dimensions of momentum (3) :  the number of elements in a basis (see basis 5) of a vector spaceb :  the quality of spatial extension :  magnitude, size … the town's modest dimensions and leisurely ways … — Jane Shellhasec :  a lifelike or realistic quality uses eccentric dialogue to add dimension to her charactersd :  the range over which or the degree to which something extends :  scope —usually used in plural the vast dimensions of the disastere :  one of the elements or factors making up a complete personality or entity :  aspect the social and political dimensions of the problem

  2. 2 obsolete :  bodily form or proportions … my dimensions are as well compact, my mind as generous, and my shape as true … — Shakespeare

  3. 3 mathematics :  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 … a secular as well as spiritual dimension … — Catherine Bates


play \-ˈmench-nəl, -ˈmen(t)-shə-nəl\ adjective


play \-ˌmen(t)-shə-ˈna-lə-tē\ noun


play \-ˈmench-nə-lē, -ˈmen(t)-shə-nəl-ē\ adverb


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.

Recent Examples of dimension from the Web

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Origin and Etymology of dimension

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

Other Mathematics and Statistics Terms



verb di·men·sion

Definition of dimension




play \-ˈmen(t)-shə-niŋ\
  1. transitive verb
  2. 1 :  to form to the required dimensions (see 1dimension 1a(1)) a table dimensioned to fit the space

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

Origin and Etymology of dimension

see 1dimension

DIMENSION Defined for English Language Learners



Definition of dimension for English Language Learners

  • : 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

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

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an extremely thin woman

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