n. pl. al·loch·thons or al·loch·tho·nes (-thə-nēz′)
1. One that originated or was formed in a place other than where it is found, especially a rock formation that has been displaced.
2. A member of a human population that relocated or was displaced from a particular area.
3. Ecology A plant or animal that is not indigenous.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2019 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.