Numerous terms are used in the English language to describe waves created in a body of water by the displacement of water; however, none of the terms in frequent use are entirely accurate.
The term tsunami, meaning "harbour wave" in literal translation, comes from the Japanese 津波, composed of the two
津 (tsu) meaning "
波 (nami), meaning "
wave". (For the plural, one can either follow ordinary English practice and add an s, or use an invariable plural as in the Japanese.
) While not entirely accurate, as tsunami are not restricted to harbours, tsunami is currently the term most widely accepted by geologists and oceanographers.
Tsunami are sometimes referred to as tidal waves.
 This once-popular term derives from the most common appearance of tsunami, which is that of an extraordinarily high
tidal bore. Tsunami and tides both produce waves of water that move inland, but in the case of tsunami the inland movement of water may be much greater, giving the impression of an incredibly high and forceful tide. In recent years, the term "tidal wave" has fallen out of favour, especially in the scientific community, because tsunami have nothing to do with
tides, which are produced by the gravitational pull of the moon and sun rather than the displacement of water. Although the meanings of "tidal" include "resembling"
 or "having the form or character of"
 the tides, use of the term tidal wave is discouraged by geologists and oceanographers.
Seismic sea wave
The term seismic sea wave also is used to refer to the phenomenon, because the waves most often are generated by
seismic activity such as earthquakes.
 Prior to the rise of the use of the term tsunami in English-speaking countries, scientists generally encouraged the use of the term seismic sea wave rather than tidal wave. However, like tsunami, seismic sea wave is not a completely accurate term, as forces other than earthquakes – including underwater
landslides, volcanic eruptions, underwater explosions, land or ice slumping into the ocean,
meteorite impacts, and the weather when the atmospheric pressure changes very rapidly – can generate such waves by displacing water.