# diameter

[dahy-am-i-ter]

### noun

Geometry.

- a straight line passing through the center of a circle or sphere and meeting the circumference or surface at each end.
- a straight line passing from side to side of any figure or body, through its center.

the length of such a line.

the width of a circular or cylindrical object.

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## RELATED WORDS

## Nearby words

- diamante,
- diamantiferous,
- diamantina,
- diamantine,
- diamanté,
- diametral,
- diametric,
- diametrical,
- diametrically,
- diamide

## Origin of diameter

Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

## Examples from the Web for diameter

## diameter

### noun

## Word Origin for diameter

C14: from Medieval Latin diametrus, variant of Latin diametros, from Greek: diameter, diagonal, from dia- + metron measure

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

late 14c., from Old French diametre, from Latin diametrus, from Greek diametros (gramme) "diagonal of a circle," from dia- "across, through" (see dia-) + metron "a measure" (see meter (n.2)).

Online Etymology Dictionary, © 2010 Douglas Harper

## diameter

[dī-ăm′ĭ-tər]

### n.

The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

## diameter

[dī-ăm′ĭ-tər]

The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

## diameter

[(deye-am-uh-tuhr)]

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

The New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.