tsunami

American  

[tsoo-nah-mee] / tsʊˈnɑ mi /

noun

1. an unusually large sea wave produced by a seaquake or undersea volcanic eruption.

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tsunami British  

/ tsʊˈnæmɪ /

noun

1. a large, often destructive, sea wave produced by a submarine earthquake, subsidence, or volcanic eruption. Sometimes incorrectly called a tidal wave

2. a sudden increase in or overwhelming number or volume of

   the tsunami of Olympic visitors

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tsunami Scientific  

/ tso̅o̅-nä′mē /

1. 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.

2. See Note at tidal wave

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tsunami Cultural  

1. A large wave on the ocean, usually caused by an undersea earthquake, a volcanic eruption, or coastal landslide. A tsunami can travel hundreds of miles over the open sea and cause extensive damage when it encounters land. Also called tidal waves.

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Other Word Forms

• tsunamic adjective

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:

• typhoon vs. tsunami
• tsunami vs. hurricane
• tidal wave vs. tsunami
• rogue wave vs. tsunami

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.

Example Sentences

In addition, the results suggest that parts of Doggerland persisted through major flooding events, including the Storegga tsunami about 8,150 years ago, with some areas remaining above water until roughly 7,000 years ago.

From Science Daily • Apr. 17, 2026

The floods are reported to have caused more destruction in Sri Lanka than the 2004 tsunami, one of the deadliest natural disasters in recorded history.

From BBC • Apr. 11, 2026

Cyclone Ditwah, the worst disaster since the 2004 Asian tsunami, killed 641 people and affected almost the entire country late last year.

From Barron's • Apr. 4, 2026

Over the past year, a global tsunami of laws and bills has been enacted or proposed that ban minors from social-media platforms or require age verification for accessing certain types of content.

From The Wall Street Journal • Mar. 27, 2026

In the town of Rikuzentakata, a single pine tree from a coastal forest of about seventy thousand trees survived the tsunami.

From "Meltdown" by Deirdre Langeland

Related Words

• deluge
• downpour
• flow
• glut
• spate
• stream
• surge
• tide
• torrent
• wave