- not formed in the region where found.Compare autochthonous(def 4).
Origin of allochthonous
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- (of rocks, deposits, etc) found in a place other than where they or their constituents were formedCompare autochthonous (def. 1)
C20: from Greek allokhthon, from allo- + khthōn (genitive khthonos) earth
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