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

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

There was a discomfort similar to waiting for a tsunami — that whatever was coming would change lives, shake institutions and make people question values and principles that they had long held dear.

From Los Angeles Times • Mar. 18, 2026

“We bear the brunt of everything. This is really a layered tsunami of hurt.”

From Salon • Mar. 17, 2026

On TikTok and Instagram, Kalshi and Polymarket have paid creators including college students to produce a tsunami of content featuring the prediction markets.

From The Wall Street Journal • Mar. 6, 2026

When a tsunami swept through in the year 869, many of the village’s residents had rushed to high ground there.

From "Meltdown" by Deirdre Langeland

Related Words

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