di·men·sion (dĭ-mĕnshən, 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).
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-2 in the Appendix of Indo-European roots.]
di·men′sion·ali·ty (-shə-nălĭ-tē) n.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.