adjective al·loch·tho·nous \-thənəs\
variants: less commonly



Definition of allochthonous

  1. 1a :  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. 2 biology :  of foreign origin :  introduced — compare autochthonous

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Origin and Etymology of allochthonous

all- + -chthonous (as in autochthonous)

First Known Use: 1888

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