ge·​oid | \ˈjē-ˌȯid \

Definition of geoid 

: the surface within or around the earth that is everywhere normal to the direction of gravity and coincides with mean sea level in the oceans

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Other Words from geoid

geoidal \jē-​ˈȯi-​dᵊl \ adjective

Examples of geoid in a Sentence

Recent Examples on the Web

The newest update, however, will use a new mean sea level reference point known as a geoid. Keith Matheny, Detroit Free Press, "Great Lakes still impacted by Ice Age phenomenon," 2 Mar. 2018

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

First Known Use of geoid

1881, in the meaning defined above

History and Etymology for geoid

German, from Greek geoeidēs earthlike, from

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Time Traveler for geoid

The first known use of geoid was in 1881

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Comments on geoid

What made you want to look up geoid? Please tell us where you read or heard it (including the quote, if possible).


to make faulty or ineffective

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