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 (dĭ-mĕn′shən, dī-)
1. A measure of spatial extent, especially width, height, or length.
2. often dimensions Extent or magnitude; scope: a problem of alarming dimensions.
3. Aspect; element: "He's a good newsman, and he has that extra dimension" (William S. Paley).
4. Mathematics
a. The least number of independent coordinates required to specify uniquely the points in a space.
b. The range of such a coordinate.
5. Physics A physical property, such as mass, distance, time, or a combination thereof, regarded as a fundamental measure of a physical quantity: Velocity has the dimension of distance divided by time.
6. A realm of existence, as in a work of fiction, that is physically separate from another such realm: "Although it tells a grounded, political story free from aliens and alternate dimensions, the film remains packed to the brim with iconic ... characters." (Conner Schwerdtfeger).
tr.v. di·men·sioned, di·men·sion·ing, di·men·sions
1. To cut or shape to specified dimensions.
2. To mark with specified dimensions.

[Middle English dimensioun, from Latin dīmēnsiō, dīmēnsiōn-, extent, from dīmēnsus, past participle of dīmētīrī, to measure out : dī-, dis-, dis- + mētīrī, to measure; see mē- in Indo-European roots.]

di·men′sion·al adj.
di·men′sion·al′i·ty (-shə-năl′ĭ-tē) n.
di·men′sion·al·ly adv.
di·men′sion·less adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
It is a dimensionless quantity defined as the one-sided leaf area per horizontal ground surface area (both in m2, namely leaf area in [m.sup.2] per 1 [m.sup.2] of surface area), and provides structural information on intensity of vegetation, like tree canopy density.
K is service factor, a dimensionless quantity that accounts for brake wear; the higher the factor, the lower the wear.
On the basis of the [pi] theorem, we selected Q, R, and c as the independent variables, and [pi] represents the dimensionless quantity [1]:
Equation (12) is derived by using the dimensionless quantity of the above definition.
Second, according to the dimensionless quantity sheet and formula (5), calculate each relevant absolute difference between reference sequence and comparative sequence and get absolute difference as shown in Table 3.
Where k is a dimensionless quantity and is known as shape factor or parameter which indicates wind stability and related to the variance of the wind speed and c is a scale factor or parameter and is associated with mean wind speed.
(8) pressure is introduced as a dimensionless quantity; in physical units the pressure P = 1 is of the order of the Young modulus.
Evidently, that the constant, [N.sub.m], has the physical dimension [N.sup.1/2] provided that the potential [[phi].sub.m](r) is a dimensionless quantity, see Example 1.