el·​lip·​soid | \ i-ˈlip-ˌsȯid How to pronounce ellipsoid (audio) , e-\

Definition of ellipsoid

: a surface all plane sections of which are ellipses or circles

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Other Words from ellipsoid

ellipsoidal \ i-​ˌlip-​ˈsȯi-​dᵊl How to pronounce ellipsoidal (audio) , (ˌ)e-​ \ or less commonly ellipsoid adjective

Examples of ellipsoid in a Sentence

Recent Examples on the Web

From radar observations, Psyche the asteroid appears ellipsoid in shape, about as wide as Massachusetts. Kenneth Chang, New York Times, "A Metal Ball the Size of Massachusetts That NASA Wants to Explore," 6 Jan. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ellipsoid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of ellipsoid

1721, in the meaning defined above

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Time Traveler for ellipsoid

The first known use of ellipsoid was in 1721

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More from Merriam-Webster on ellipsoid

Rhyming Dictionary: Words that rhyme with ellipsoid

Britannica.com: Encyclopedia article about ellipsoid

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