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allochthonous

American  
[uh-lok-thuh-nuhs] / əˈlɒk θə nəs /

adjective

Geology.

  1. not formed in the region where found.

allochthonous British  
/ əˈlɒkθənəs /

adjective

  1. (of rocks, deposits, etc) found in a place other than where they or their constituents were formed Compare autochthonous

"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 allochthonous

1910–15; allo- + -chthonous, modeled after autochthonous

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

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.