n. 1. an unusually high wave from the sea, sometimes reaching far inland and causing great destruction, and usually caused by some event, such as an earthquake, far from the shore. In Japan, such a wave is called a tsunami. [ PJC ]

2. [ fig. ] an unusually large quantity of items or events requiring attention and causing strain on the capacity to handle them; as, a tidal wave of orders for a new product; a tidal wave of tourists. [ PJC ]