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ultrabasic

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