noun or·tho·gneiss \ˈȯ(r)thə+ˌ-\

Definition of orthogneiss

  1. :  gneiss derived from an igneous rock

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Origin and Etymology of orthogneiss

German orthogneis, from orth- + gneis gneiss — more at gneiss

Seen and Heard

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a rounded knoll or a ridge of ice

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