conchoidal

American

[kong-koid-l] / kɒŋˈkɔɪd l /

adjective

Mineralogy.

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

conchoidal British

/ kɒŋˈkɔɪdəl /

adjective

(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

conchoidal Scientific

/ kŏng-koid′l /

Of or relating to a mineral or rock surface that is characterized by smooth, shell-like curves. Obsidian and quartz often have conchoidal fractures.

Other Word Forms

Etymology

Origin of conchoidal

First recorded in 1660–70; conchoid + -al ¹

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A conchoidal fracture has a smooth, curved surface like a shallow bowl or conch shell, often with curved ridges.

From Textbooks • Jan. 1, 2017

Mineral fracture surfaces may be rough, uneven, or show a conchoidal fracture.

From Textbooks • Jan. 1, 2017

Words flunked: dioceses, cantatrice, Nabuchodonosor, a fortiori, conchoidal.

From Time Magazine Archive

This cement, where it abounds, has a conchoidal fracture and passes to jasper.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3 by Humboldt, Alexander von

Their surfaces often show minute crescentic or rounded cracks which are the edges of small conchoidal fractures produced by the impact of one pebble on another during storms or floods.

From Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 5 "Fleury, Claude" to "Foraker" by Various

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023