1. A deep wide ditch, usually filled with water, typically surrounding a fortified medieval town, fortress, or castle as a protection against assault.
2. A ditch similar to one surrounding a fortification: A moat separates the animals in the zoo from the spectators.
tr.v. moat·ed, moat·ing, moats
To surround with or as if with a moat.
[Middle English mote, mound, moat (since both mounds and moats form part of fortifications), from Old French, mound; akin to Medieval Latin mota, perhaps of Germanic origin and akin to English MUD.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 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.