WordReference Random House Learner's Dictionary of American English © 2026
di•men•sion /dɪˈmɛnʃən/USA pronunciation
n. [countable]
WordReference Random House Unabridged Dictionary of American English © 2026- Mathematicsa property of space;
extension of a line in a given direction:A straight line has one dimension, a square has two dimensions, and a cube has three dimensions. - Usually, dimensions. [plural] measurement in length, width, and thickness;
size:Let's figure out the dimensions of the room to see how much paint we will need. - an aspect or factor (of a situation) to be considered;
side:The kiss they shared under the bridge added a new dimension to their relationship. - Usually, dimensions. [plural] the scope or importance (of a problem or situation);
magnitude;
size:No one understood the dimensions of the problem.
di•men•sion
(di men′shən, dī-),USA pronunciation n.
v.t.
di•men′sion•al, adj.
di•men′sion•al′i•ty, n.
di•men′sion•al•ly, adv.
di•men′sion•less, adj.
- Mathematics
- 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. - the generalization of this property to spaces with curvilinear extension, as the surface of a sphere.
- the generalization of this property to vector spaces and to Hilbert space.
- the generalization of this property to fractals, which can have dimensions that are noninteger real numbers.
- extension in time:Space-time has three dimensions of space and one of time.
- a property of space;
- Weights and MeasuresUsually, dimensions.
- measurement in length, width, and thickness.
- scope;
importance:the dimensions of a problem.
- Weights and Measuresunit (def. 6).
- Weights and Measuresmagnitude;
size:Matter has dimension. - Mathematics[Topology.]
- 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.
- the number of elements in a finite basis of a given vector space.
- Physicsany 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]. Cf. dimensional analysis. - Informal Terms dimensions, the measurements of a woman's bust, waist, and hips, in that order:The chorus girl's dimensions were 38-24-36.
- BuildingSee dimension lumber.
v.t.
- Buildingto shape or fashion to the desired dimensions:Dimension the shelves so that they fit securely into the cabinet.
- to indicate the dimensions of an item, area, etc., on (a sketch or drawing).
- 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
- Anglo-French)
- late Middle English dimensioun (1375–1425
di•men′sion•al′i•ty, n.
di•men′sion•al•ly, adv.
di•men′sion•less, adj.
- 2. b. range, extent, magnitude.
'dimensions' also found in these entries (note: many are not synonyms or translations):
array
- bill of quantities
- by
- calliper
- commensurable
- construction
- cubic
- deform
- deformation
- die
- dimension
- document
- dummy
- expansion
- fourth dimension
- full-scale
- golden section
- hatchet
- hyperspace
- isometric
- lattice
- mechanical drawing
- module
- nanoparticle
- nanophysics
- nanotechnology
- pelvimetry
- perspective
- point
- point source
- proportion
- rating
- resistivity
- scantling
- size
- solid
- stereoscopy
- stereovision
- subatomic
- telephoto lens
- three-dimensional
- two-dimensional
- admeasure
- admeasurement
- allowance
- anisotropic
- arcature
- assembly
- attenuation
- bandbox