variants or less commonly allocthonous
: of or relating to the rocks of an allochthon
of coal : formed elsewhere than in situ and hence not autochthonous
of limestone : composed largely of organic debris moved far from the place where the base organisms lived
biology : of foreign origin : introduced compare autochthonous

Word History


all- + -chthonous (as in autochthonous)

First Known Use

1888, in the meaning defined at sense 1a

Time Traveler
The first known use of allochthonous was in 1888

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Dictionary Entries Near allochthonous

Cite this Entry

“Allochthonous.” Dictionary, Merriam-Webster, Accessed 13 Jun. 2024.

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