An underground passageway, chamber, or series of chambers, sometimes having a roof of stone slabs, built as part of an ancient settlement or fort, especially in the British Isles.
[Earlier, any underground passage or storeroom, from French, from Old French, sozterrain (formed on the model of Latin subterrāneus, underground) : soz, under (from Latin subtus, from sub; see upo in the Appendix of Indo-European roots) + terre, earth (from Latin terra; see ters- in the Appendix of Indo-European roots).]
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.