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trappean

British  
/ ˈtræpɪən, trəˈpɪən /

adjective

  1. rare of, relating to, or consisting of igneous rock, esp a basalt

"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

Etymology

Origin of trappean

C19: from trap ³

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.

These tuffs, and the associated trappean rocks, must not be compared to lava and scoriae which had cooled in the open air.

From The Student's Elements of Geology by Lyell, Charles, Sir

The geological formation consists largely of primitive or igneous rocks, trappean, basaltic and granite, and the scenery has a peculiarly grand and sombre appearance.

From Fifty Years In The Northwest With An Introduction And Appendix Containing Reminiscences, Incidents And Notes by Folsom, William Henry Carman

If the term "overlying" can in this instance be applied to a Plutonic rock, it is only in proportion as that rock begins to acquire a trappean aspect.

From The Student's Elements of Geology by Lyell, Charles, Sir

We first crossed more hills of the trappean conglomerate on which grew ironbark eucalypti and box.

From Three Expeditions into the Interior of Eastern Australia, Volume 2 by Mitchell, Thomas

What is the difference between trappean breccia and trappean conglomerate?

From Geology by Geikie, James