Definition of dimension
(Entry 1 of 2)
1a mathematics
(1) : measure in one direction
the dimensions of the room specifically : one of three coordinates (see coordinate entry 3 sense 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 sense 1) or coordinate variable assigned to such a property the three dimensions of momentum
(3) : the number of elements in a basis (see basis sense 5) of a vector space
c : a lifelike or realistic quality
uses eccentric dialogue to add dimension to her characters
d : the range over which or the degree to which something extends : scope —usually used in pluralthe vast dimensions of the disaster
e : one of the elements or factors making up a complete personality or entity : aspect the social and political dimensions of the problem
2 obsolete : bodily form or proportions
… my dimensions are as well compact, my mind as generous, and my shape as true …— Shakespeare
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 : wood or stone cut to pieces of specified size
5 : a level of existence or consciousness
… a secular as well as spiritual dimension …— Catherine Bates
dimension
verbDefinition of dimension (Entry 2 of 2)
1 : to form to the required dimensions (see dimension entry 1 sense 1a(1))
a table dimensioned to fit the space
2 : to indicate the dimensions of (as on a drawing)
dimensioning the plans
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Time Traveler for dimension
The first known use of dimension was in the 14th century
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