Tsunami and Tidal wave

Tsunami noun - A cataclysm resulting from a destructive sea wave caused by an earthquake or volcanic eruption.

Tidal wave and tsunami are semantically related In some cases you can use "Tidal wave" instead a noun "Tsunami".

Tidal wave noun - An unusual (and often destructive) rise of water along the seashore caused by a storm or a combination of wind and high tide.

Tsunami and tidal wave are semantically related in giant sea wave topic. You can use "Tsunami" instead a noun phrase "Tidal wave".