ultrabasic
[ uhl-truh-bey-sik ]
/ ˌʌl trəˈbeɪ sɪk /
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adjective
(of rocks) containing iron and magnesium, with little or no silica.
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Also ultramafic.
Words nearby ultrabasic
ultimo, ultimogeniture, ultisol, ulto., ultra, ultrabasic, ultracentrifuge, ultraclean, ultraconservative, ultracrepidarian, ultracritical
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
Example sentences from the Web for ultrabasic
These range from acid to ultrabasic types and include granite, augite-diorite, picrite and serpentine.
British Dictionary definitions for ultrabasic
ultrabasic
/ (ˌʌltrəˈbeɪsɪk) /
adjective
(of such igneous rocks as peridotite) containing less than 45 per cent silica
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Scientific definitions for ultrabasic
ultrabasic
[ ŭl′trə-bā′sĭk ]
Containing magnesium and iron and only a very small amount of silica. Used of igneous rock, and often used interchangeably with ultramafic. Peridotite is an ultrabasic rock.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.