allochthonous

adjective

al·​loch·​tho·​nous

variants or less commonly allocthonous

-thənəs

1

a

: of or relating to the rocks of an allochthon

b

of coal : formed elsewhere than in situ and hence not autochthonous

c

of limestone : composed largely of organic debris moved far from the place where the base organisms lived

2

biology : of foreign origin : introduced compare autochthonous

Word History

Etymology

all- + -chthonous (as in autochthonous)

First Known Use

1888, in the meaning defined at sense 1a

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