tsunami
Americannoun
noun
-
a large, often destructive, sea wave produced by a submarine earthquake, subsidence, or volcanic eruption. Sometimes incorrectly called a tidal wave
-
a sudden increase in or overwhelming number or volume of
the tsunami of Olympic visitors
-
A very large ocean wave that is caused by an underwater earthquake or volcanic eruption and often causes extreme destruction when it strikes land. Tsunamis can have heights of up to 30 m (98 ft) and reach speeds of 950 km (589 mi) per hour. They are characterized by long wavelengths of up to 200 km (124 mi) and long periods, usually between 10 and 60 minutes.
-
See Note at tidal wave
Other Word Forms
Etymology
Origin of tsunami
1905–10; < Japanese, equivalent to tsu harbor (earlier tu ) + nami wave
Compare meaning
How does tsunami compare to similar and commonly confused words? Explore the most common comparisons:
Explanation
A tsunami is an enormous sea wave that erupts and reaches land. You should be afraid of them, because a tsunami can destroy a coastal region in minutes. Japan has had the misfortune of experiencing many tsunamis. They're caused by earthquakes or volcanic eruptions under the sea. In Japanese, tsu means "harbor" and nami means "wave." We sometimes use tsunami metaphorically, to describe really destructive events. After your parents came home, they compared the mess from your party to a tsunami.
Vocabulary lists containing tsunami
The Absolutely True Diary of a Part-Time Indian
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Physical Geography - Introductory
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Brace Yourself: Earthquake Words
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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.
Among Indonesia's history of deadly quakes is a devastating 9.1-magnitude tremor in 2004 that struck off the coast of Sumatra and triggered a tsunami that killed 220,000 throughout the region, including about 170,000 in Indonesia.
From Barron's ● Aug. 15, 2026
A strong 7.7-magnitude earthquake struck off Flores island in eastern Indonesia early Saturday, sending thousands running in panic after authorities issued a tsunami warning.
From Barron's ● Aug. 15, 2026
A stream of people could be seen moving inland on motorbikes after authorities issued a tsunami warning.
From BBC ● Aug. 15, 2026
A tsunami warning was later lifted but people were warned not to return to damaged buildings for fear that aftershocks may bring them down.
From Barron's ● Aug. 15, 2026
Some went to evacuation centers, only to find that the centers were in the path of the tsunami.
From "Meltdown" by Deirdre Langeland
![]()
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.