tidal wave

• enPR: tīd'əl wāv, IPA^(key): /ˈtaɪdəlweɪv/

• Audio (US)

  (file)

tidal wave (plural tidal waves)

1. A large and sudden rise and fall in the tide.
2. (proscribed) A large, sudden, and disastrous wave of water caused by a tremendous disturbance in the ocean; a tsunami. (See Usage notes below.)

   The last tidal wave here killed twenty and left thousands homeless.

3. (proscribed) A large, sudden inundation of water from the storm surge, or waves of that surge; a sudden surge of river water.
   • 1961 January, “Talking of Trains: Flooding at Lewes”, in Trains Illustrated, page 5:

     During the day conditions worsened quickly—for example, a 2-6-0 on the Uckfield line suddenly encountered flood water high enough to enter its ashpan and extinguish its fire—until lock gates up-river at Barcombe gave way and a tidal wave rolled down the valley meeting head-on a spring tide rolling up from the coast.

4. (figuratively) A sudden and powerful surge.

   As the doors opened, a tidal wave of people flooded into the room.

   I was overcome by a tidal wave of emotions.

   • 2003, Michael Moore, chapter 3, in Dude, Where’s My Country:

     But this is no stream, folks. This will be a tidal wave that can swamp our democracy.

5. (archaic) A crest of ocean water; a wave.
6. (oceanography) A crest of ocean water resulting from tidal forces.

• For some time now, it has been common to correct the use of tidal wave that refers to a disastrous wave caused by a disturbance in the ocean, with the term tsunami suggested in its stead. In scientific publications, tsunami has become the standard term for this phenomenon, though in the mass media and elsewhere, they are used interchangeably and frequently, tsunami seeing more usage on the whole.

• The sense of tidal wave that is synonymous with tsunami has long been in the English language, and relates to the uncommon sense of tidal that refers to any rise and fall in the water level of any large body of water, and not just the daily rising and falling caused by the moon (see storm tide, hurricane tide, and tidal flood). While there is nothing that is strictly speaking ‘incorrect’ with regard to this usage of tidal wave, many people believe that the term should simply not be linked with the term tide at all, to avoid the possibility of any confusion as to the cause of a tidal wave.

• Tsunami was at one point strongly associated with scientific use, and many people would have considered it pedantic in ordinary conversation, but its prevalence in mass media and popular media has most likely reduced or eliminated this association. Currently it is a (mostly) non-contentious term that can be used in place of the more contentious and oft-corrected tidal wave.

• For quotations using this term, see Citations:tidal wave.

• tidal bore
• tidal surge

• earthquake
• flood