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ultrabasic

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adjective ul·tra·ba·sic \ˌəl-trə-ˈbā-sik\

Definition of ultrabasic

: extremely basic an ultrabasic system; specifically : very low in silica and rich in iron and magnesium minerals dunite and peridotite are ultrabasic rocks

ultrabasic

noun

Origin and Etymology of ultrabasic

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First Known Use: 1881

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