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

Definition of waterloo

 (Entry 1 of 2)

: a decisive or final defeat or setback a political waterloo


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

Definition of Waterloo (Entry 2 of 2)

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

Did You Know?

The Battle of Waterloo, which occurred on June 18, 1815, has given its name to the very notion of final defeat. Why? Maybe because it ended one of the most spectacular military careers in history (Napoleon's), as well as 23 years of recurrent conflict between France and the rest of Europe. In addition, it was Napoleon's second "final defeat." He was defeated and exiled in 1814, but he escaped his confinement, returned to France, and was restored to power for three months before meeting defeat at the hands of the forces allied under the Duke of Wellington near the Belgian village of Waterloo. The word waterloo first appeared in casual use the following year, 1816.

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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