wave. Living near the ocean, watching tides and waves, it is not that at all but the ocean coming in and in and in and in and in. A really fast really big tide with a hell of a lot of energy driving it.

And then it is not water but houses, cars, debris, branches, all sort of shit pressing in. Incredible video and

"Tsunami waves topped 60 feet or more as they broke onshore following Japan’s earthquake, according to some of the first surveys measuring the impact along the afflicted nation’s entire coast. Some waves grew to more than 100 feet high, breaking historic records, as they squeezed between fingers of land surrounding port towns."

http://usatoday30.usatoday.com/news/world/2011-04-24-Japan-record-tsunami-waves.htm

is any sea wave that is generated by a seismic event. I remember seeing a live broadcast of a tsunami on Japanese TV several years before the 2011 disaster, and in that case it was indistinguishable from a regular sea wave.