noun sy·e·no·diorite \¦sīəˌnō+\

Definition of syenodiorite

  1. :  a plutonic rock composed of acid plagioclase, less orthoclase, and a ferromagnesian mineral — compare granodiorite

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Origin and Etymology of syenodiorite

syenite + -o- + diorite

Seen and Heard

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a rounded knoll or a ridge of ice

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