moat
Americannoun
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a deep, wide trench, usually filled with water, surrounding the rampart of a fortified place, such as a town or a castle.
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any trench, such as one used for confining animals in a zoo.
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a competitive advantage a business has in its field.
The company's moat was reduced when the patent on the devices they sold expired.
noun
verb
Etymology
Origin of moat
First recorded in 1325–75; Middle English mote, from Old French: “clod, mound,” of obscure origin
Explanation
Not many houses these days have a moat — it's a trench dug outside a castle and is usually full of water. A moat means "Keep out!" You're most likely to hear about moats if you read a fairy tale or a history of medieval times. This water-filled ditch is one of the lines of defense for a castle. In the old days, it was pretty effective. If you filled the moat with a deadly fish — like a piranha — that was an even better defense. A moat is pretty much the opposite of a welcome mat.
Vocabulary lists containing moat
The One and Only Ivan
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The Roman and Byzantine Empires, Lessons 5–7
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Shouting at the Rain
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Macy’s ultimate moat might be the physical shopping experience, which is making a comeback.
From The Wall Street Journal • Jun. 4, 2026
Creating reliable space technology isn’t easy, which is one reason SpaceX has a huge competitive moat.
From Barron's • May 22, 2026
Creating reliable space technology isn’t easy, which is one reason SpaceX has a huge competitive moat.
From Barron's • May 22, 2026
“The narrative is the moat is eroding and the space becoming commoditized,” Konik said.
From MarketWatch • May 8, 2026
A dry moat, several yards wide and equally deep.
From "Without Refuge" by Jane Mitchell
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
