noun ge·oid \ˈjē-ˌȯid\

Definition of geoid

  1. :  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


play \jē-ˈȯi-dəl\ adjective

Origin and Etymology of geoid

German, from Greek geoeidēs earthlike, from

First Known Use: 1881

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