Where does the word tsunami come from?
Quick answer
Tsunami comes from Japanese: tsu (津) means “harbor” and nami (波) means “wave,” so a tsunami is a “harbor wave.” Fishermen are said to have named it after returning from open sea, where they hadn’t noticed anything, to find their harbors destroyed. Japan has a long history of these waves.
Why “harbor wave”?
Out in deep ocean, a tsunami may be less than a meter high and travel at the speed of a jet plane, about 800 km/h (500 mph). Ships barely feel it pass. As it reaches shallow water near the coast, it slows down and piles up, sometimes into a wall of water many meters tall.
Not a “tidal wave”
English speakers used to call them tidal waves, but tsunamis have nothing to do with tides. Scientists adopted the Japanese word to avoid confusion, and it became common worldwide after the 2004 Indian Ocean tsunami.
What causes tsunamis
| Cause | Example |
|---|---|
| Undersea earthquakes (most common) | 2011 Tōhoku, Japan |
| Volcanic eruptions | 1883 Krakatoa; 2022 Hunga Tonga |
| Landslides | 1958 Lituya Bay, Alaska (wave ran up 524 m) |
| Meteorite impacts | Chicxulub impact, 66 million years ago |
Earthquakes are studied in seismology.
Deadly tsunamis
| Year | Event | Notes |
|---|---|---|
| 2004 | Indian Ocean | About 230,000 deaths in 14 countries |
| 2011 | Tōhoku, Japan | About 18,000 deaths; Fukushima nuclear accident |
| 1755 | Lisbon | Earthquake, tsunami and fire devastated the city |
Warning signs
Official advice is that if you’re near the coast and feel a strong earthquake, or see the sea suddenly draw back far from the shore, move to high ground right away instead of waiting for a warning.
Other Japanese words in English
Karaoke (“empty orchestra”), emoji (“picture character”), typhoon (partly), tycoon (“great lord”) and origami (“folding paper”).
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