The story
1940–45; back formation from allochthonous.
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A geological formation not formed in the region where found and moved to its present location by tectonic forces. Compare autochthon. Full definition →
1940–45; back formation from allochthonous.
Etymology from Wiktionary, CC BY-SA 4.0.