An overpowering deluge of rain.

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1821.  This deluge, which they call the bursting of a cloud, took place in Oct. 1784.—T. Dwight, ‘Travels,’ iii. 249.

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1881.  [The village] was nearly annihilated by a water-spout or a cloud-burst.Chicago Times, June 11. (N.E.D.)

3