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]
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]

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THESAURUS

tidal wave

amplitude, antinode, apoplexy, billow, bore, breakers, breakup, cataclysm, chop, choppiness, chopping sea, climax, comb, comber, convulsion, count, crest, de Broglie wave, diastrophism, diffraction, dirty water, disaster, eagre, election returns, electromagnetic radiation, electromagnetic wave, fit, frequency, frequency band, frequency spectrum, gravity wave, ground swell, guided wave, heave, heavy sea, heavy swell, in phase, interference, landslide, lift, light, longitudinal wave, lop, mechanical wave, node, official count, out of phase, overthrow, paroxysm, peak, period, periodic wave, poll, popple, quake, radio wave, ray, recount, reinforcement, resonance, resonance frequency, returns, riffle, ripple, rise, roll, roller, rough water, scend, sea, seismic wave, send, shock wave, sound wave, spasm, stroke, surf, surface wave, surge, swell, temblor, tidal bore, tide wave, transverse wave, trough, tsunami, undulation, upheaval, water wave, wave, wave equation, wave motion, wave number, wavelength, wavelet, white horses, whitecaps

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