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Synonyms

diameter

American  
[dahy-am-i-ter] / daɪˈæm ɪ tər /

noun

  1. Geometry.

    1. a straight line passing through the center of a circle or sphere and meeting the circumference or surface at each end.

    2. a straight line passing from side to side of any figure or body, through its center.

  2. the length of such a line.

  3. the width of a circular or cylindrical object.


diameter British  
/ daɪˈæmɪtə /

noun

    1. a straight line connecting the centre of a geometric figure, esp a circle or sphere, with two points on the perimeter or surface

    2. the length of such a line

  1. the thickness of something, esp with circular cross section

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

diameter Scientific  
/ dī-ămĭ-tər /
  1. A straight line segment that passes through the center of a circle or sphere from one side to the other.

  2. The length of such a line segment.


diameter Cultural  
  1. A straight line passing through the center of a figure, especially a circle or sphere, and joining two opposite points on its circumference.


Etymology

Origin of diameter

First recorded in 1350–1400; Middle English diametre, from Old French, from Latin diametros, from Greek diámetros “diagonal, diameter,” from dia- dia- + -metros, derivative of métron meter 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Measuring roughly 55 feet long and 18 feet wide, the float featured a dense seascape of corals, fish and oversize sea stars, some spanning 4 feet in diameter.

From Los Angeles Times

The tests ranged from six-to-12m in diameter to represent house platforms of different sizes.

From BBC

When fully developed, the organoids reached about three millimeters in diameter.

From Science Daily

Built-in guides help you gauge precisely the diameter of your logs and make consistent slices, turning out treats that impress type-A bakers every time.

From The Wall Street Journal

The tubes measure about 230 nm in diameter and are made of 5 to 6 right-handed helical fibers that twist together.

From Science Daily