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uprush

American  
[uhp-ruhsh] / ˈʌpˌrʌʃ /

noun

  1. an upward rush, as of water or air.

  2. an abrupt increase.

    an uprush of business during the noon hour.


uprush British  
/ ˈʌpˌrʌʃ /

noun

  1. an upward rush, as of consciousness

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of uprush

First recorded in 1870–75; up- + rush 1