a hollow concretionary or nodular stone often lined with crystals.
the hollow or cavity of this.
any similar formation.
- ge·od·ic [jee-od-ik], /dʒiˈɒd ɪk/, ge·od·al [jee-ohd-l], /dʒiˈoʊd l/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use geode in a sentence
These geodes, on breaking, often present a mammillary surface.Summary Narrative of an Exploratory Expedition to the Sources of the Mississippi River, in 1820 | Henry Rowe Schoolcraft
I have since learned that such stones are found at many points, and that they are called geodes.Death Valley in '49 | William Lewis Manly
Many sorts there are of this ratling Stone, beside the Geodes, containing a softer substance in it.The Works of Sir Thomas Browne (Volume 1 of 3) | Thomas Browne
This was a strange place, and in our search we found geodes, petrified snakes, and short sections of fish.The Sheep Eaters | William Alonzo Allen
Besides quartz crystals, others of calcareous spar are sometimes found in the cavities of geodes.The Chautauquan, Vol. III, March 1883 | The Chautauquan Literary and Scientific Circle
British Dictionary definitions for geode
a cavity, usually lined with crystals, within a rock mass or nodule
- geodic (dʒɪˈɒdɪk), adjective
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for geode
A small, hollow, usually rounded rock lined on the inside with inward-pointing crystals. Geodes form when mineral-rich water entering a cavity in a rock undergoes a sudden change in pressure or temperature, causing crystals to form from the solution and line the cavity's walls.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.