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di·am·e·ter  (di-ami-tər)
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Tweet n. 1. Abbr. d or diam.Mathematics a. A straight line segment passing through the center of a figure, especially of a circle or sphere, and terminating at the periphery. b. The length of such a segment. 2. Thickness or width. 3. A unit of magnification equal to the number of times an object's linear dimensions is increased by the magnifying apparatus. [Middle Englishdiametre, fromOld French, fromLatindiametrus, fromGreekdiametros (gramme), diagonal (line) : dia-, dia- + metron, measure; see me-2 in the Appendix of Indo-European roots.] di·ame·tral(-trəl)adj.  (click for a larger image) diameter |
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