noun, often capitalized
wa·​ter·​loo | \ ˌwȯ-tər-ˈlü How to pronounce waterloo (audio) , ˌwä- \
plural waterloos

Definition of waterloo

: a decisive or final defeat or setback a political waterloo

Examples of waterloo in a Sentence

Recent Examples on the Web The waterloo arrived in 1930, with the Smoot-Hawley tariff. Jay Cost, National Review, 14 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'waterloo.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of waterloo

1816, in the meaning defined above

History and Etymology for waterloo

Waterloo, Belgium, scene of Napoleon's defeat in 1815

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The first known use of waterloo was in 1816

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Cite this Entry

“Waterloo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/waterloo. Accessed 28 Sep. 2022.

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More Definitions for waterloo

Waterloo geographical name

Wa·​ter·​loo | \ ˌwȯ-tər-ˈlü How to pronounce Waterloo (audio) , ˌwä-; ˈwȯ-tər-ˌlü, ˈwä- \

Definition of Waterloo

1 city in northeast central Iowa northwest of Cedar Rapids population 68,406
2 town in central Belgium south of Brussels population 28,898

Note: In June 1815, a battle near Waterloo resulted in the decisive defeat of French Emperor Napoléon I.

3 city in southeastern Ontario, Canada, west of Kitchener population 98,780

More from Merriam-Webster on waterloo

Britannica.com: Encyclopedia article about waterloo


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