A large wave can be described in various ways depending on its intensity and movement. Some synonyms for a large wave include tsunami, tidal wave, breaker, surging water, roller, swell, wall of water, cascading wave, mountainous wave, and towering wave. A tsunami is a giant wave caused by underwater earthquakes, while a tidal wave is a large wave caused by the gravitational forces of the moon and the sun. A breaker is a wave that is about to crash onto land, while a roller is a long and smooth wave that is perfect for surfing. Swell, on the other hand, is a large and consistent wave that travels across the ocean.