The word 'tsunami' originates from which language?

The word “tsunami” originates from Japanese. It comes from the Japanese words tsu, meaning “harbour,” and nami, meaning “wave,” so the literal translation is “harbour wave.” The term entered English as a borrowing from Japanese and is now the standard scientific and everyday word for these long-wavelength waves.

The name reflects how a tsunami can appear especially dramatic in a harbour or coastal inlet. In the open ocean, a tsunami may have a low wave height and pass beneath ships with little visible effect. As it reaches shallow water, the wave slows, compresses, and grows taller, allowing it to surge inland.

A frequent mistake is calling a tsunami a “tidal wave.” Tsunamis are not caused by tides or the Moon’s gravitational pull. They are generated by the sudden displacement of a large volume of water, most often after an undersea earthquake.

English speakers may pronounce the initial t weakly or omit it, but the original Japanese pronunciation includes the sound. In English, both “tsunamis” and the Japanese-style uninflected plural “tsunami” are encountered, although “tsunamis” is common.