dimension

American  

[dih-men-shuhn, dahy-] / dɪˈmɛn ʃən, daɪ- /

noun

1. Mathematics.

   1. a property of space; extension in a given direction.

      A straight line has one dimension, a parallelogram has two dimensions, and a parallelepiped has three dimensions.

   2. the generalization of this property to spaces with curvilinear extension, as the surface of a sphere.

   3. the generalization of this property to vector spaces and to Hilbert space.

   4. the generalization of this property to fractals, which can have dimensions that are noninteger real numbers.

   5. extension in time.

      Space-time has three dimensions of space and one of time.

2. Usually dimensions.

   1. measurement in length, width, and thickness.

   2. scope; importance.

      the dimensions of a problem.

3. an aspect, feature, or angle: We haven't addressed that dimension of the issue.

   A study abroad experience can add a cultural dimension to your language learning.

   We haven't addressed that dimension of the issue.

4. unit.

5. magnitude; size.

   Matter has dimension.

6. Topology.

   1. a magnitude that, independently or in conjunction with other such magnitudes, serves to define the location of an element within a given set, as of a point on a line, an object in a space, or an event in space-time.

   2. the number of elements in a finite basis of a given vector space.

7. Physics. any of a set of basic kinds of quantity, as mass, length, and time, in terms of which all other kinds of quantity can be expressed: usually denoted by capital letters, with appropriate exponents, placed in brackets.

   The dimensions of velocity are [LT−1].

8. Also called alternate dimension.  (in science fiction, fantasy, etc.) a hypothetical universe or world that is different from our known universe and reachable by traveling in directions that are not the perceptible axes of space and time, as with the use of futuristic technology or magic.

   Your enemies are villains, cultists, terrible monsters, and unfathomable entities from alternate dimensions or the cosmos beyond.

9. Informal. dimensions, the measurements of a woman's bust, waist, and hips, in that order.

   The dressmaker noted that the customer's dimensions were 38-24-36.

10. dimension lumber.

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verb (used with object)

1. to shape or fashion to the desired dimensions.

   Dimension the shelves so that they fit securely into the cabinet.

2. to indicate the dimensions of an item, area, etc., on (a sketch or drawing).

dimension British  

/ dɪˈmɛnʃən /

noun

1. (often plural) a measurement of the size of something in a particular direction, such as the length, width, height, or diameter

2. (often plural) scope; size; extent

   a problem of enormous dimensions

3. aspect

   a new dimension to politics

4. maths the number of coordinates required to locate a point in space

5. physics

   1. the product or the quotient of the fundamental physical quantities (such as mass, length, or time) raised to the appropriate power in a derived physical quantity

      the dimensions of velocity are length divided by time

   2. the power to which such a fundamental quantity has to be raised in a derived quantity

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verb

1. (tr)

   1. to shape or cut to specified dimensions

   2. to mark with specified dimensions

dimension Scientific  

/ dĭ-mĕn′shən /

1. 1. Any one of the three physical or spatial properties of length, area, and volume. In geometry, a point is said to have zero dimension; a figure having only length, such as a line, has one dimension; a plane or surface, two dimensions; and a figure having volume, three dimensions. The fourth dimension is often said to be time, as in the theory of General Relativity. Higher dimensions can be dealt with mathematically but cannot be represented visually.

   2. The measurement of a length, width, or thickness.

2. A unit, such as mass, time, or charge, associated with a physical quantity and used as the basis for other measurements, such as acceleration.

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Other Word Forms

• dimensional
  adjective
• dimensionality
  noun
• dimensionally
  adverb
• dimensionless
  adjective
• multidimensional
  adjective
• nondimensioned
  adjective
• undimensioned
  adjective

Etymology

Origin of dimension

First recorded in 1375–1425; late Middle English dimensioun, from Anglo-French or directly from Latin dīmēnsiōn- (stem of dīmēnsiō ) “a measuring,” equivalent to dīmēns(us) “measured out” (past participle of dīmētīrī, equivalent to dī- di- ² + mētīrī “to measure”) + -iōn- -ion

Explanation

A dimension is the measurement of something in physical space. You might give the painters every dimension of the rooms you want painted, including depth, height, and width. In addition to physical objects, dimension can describe something less tangible, such as the magnitude or extent of something. You might be shocked by the dimension of damage from the explosion down the street. Dimension can also be a feature of something, such as an experience, situation, flavor, or thing. Painting your bedroom purple will add a mystical dimension to your dwelling, especially if you add unicorn accents.

Example Sentences

He was a founding member of the vocal group the 5th Dimension, which won six Grammy Awards for songs such as “Up, Up and Away” and “Aquarius/Let the Sunshine In.”

From Los Angeles Times • Feb. 11, 2026

Back in January, the cast of Dimension 20 pulled off something no tabletop RPG show had ever done: they sold out Madison Square Garden.

From Salon • Jun. 28, 2025

If you haven't been flexing those dance moves yet, then get ready to bring them out when Dimension takes to the new music stage.

From BBC • May 24, 2024

The maker of 3D printers received an increased buyout offer from Nano Dimension of $16.50 per share in cash.

From Seattle Times • Dec. 26, 2023

For all I knew, he stepped off that bus every afternoon and was whooshed into Dimension X—which might have explained a thing or two about his personality.

From "Schooled" by Gordon Korman

Related Words

• aspect
• element
• extent
• height
• importance
• length
• magnitude
• proportion
• quality
• range
• scope
• size
• thickness