[ kong-koid-l ]
/ kɒŋˈkɔɪd l /

adjective Mineralogy.

noting a shell-like fracture form produced on certain minerals by a blow.


Discover The Influence Of Portuguese On English Via This Quiz!
We’ve gathered some interesting words donated to English from Portuguese … as well as some that just don’t translate at all. Do you know what they mean?
Question 1 of 11
Which of the following animal names traces its immediate origin to Portuguese?

Origin of conchoidal

First recorded in 1660–70; conchoid + -al1


con·choi·dal·ly, adverbsub·con·choi·dal, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for conchoidal

British Dictionary definitions for conchoidal

/ (kɒŋˈkɔɪdəl) /


(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

Derived forms of conchoidal

conchoidally, adverb
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 conchoidal

[ kŏng-koidl ]

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 Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.