noting a shell-like fracture form produced on certain minerals by a blow.
Origin of conchoidal
Related formscon·choi·dal·ly, adverbsub·con·choi·dal, adjective
First recorded in 1660–70; conchoid
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for conchoidal
Historical Examples of conchoidal
I noticed some conchoidal hollows more than a foot in diameter.
It has a conchoidal fracture, and is without smell or taste.
Their fracture is conchoidal, with hmatitic (iron-ore pimpled) surface.
When of good quality it is too hard to be scratched by the nail, has a conchoidal fracture, and a sp.
In colour they vary from ash-grey to black, and their fracture is conchoidal.
British Dictionary definitions for conchoidal
Derived Formsconchoidally, adverb
(of the fracture of minerals and rocks) having smooth shell-shaped convex and concave surfaces
(of minerals and rocks, such as flint) having such a fracture
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
Of or relating to a mineral or rock surface that is characterized by smooth, shell-like curves. Obsidian and quartz often have conchoidal fractures.
The American Heritage® Science Dictionary
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