We use cookies to enhance your experience on our website. By continuing to use our website, you are agreeing to our use of cookies. You can change your cookie settings at any time. Find out more

Subscriber login

Library card login

Other

X Close menu

Dictionary Language resources

diameter

Pronunciation: /dʌɪˈamɪtə/

Translate diameter | into French | into German | into Italian | into Spanish

Definition of diameter

noun

1a straight line passing from side to side through the centre of a body or figure, especially a circle or sphere.
a transverse measurement of something; width or thickness.

2a unit of linear measurement of magnifying power.

Derivatives

diametral

Origin:

late Middle English: from Old French diametre, via Latin from Greek diametros (grammē) '(line) measuring across', from dia 'across' + metron 'measure'