verb (used with object)

to strike or beat vigorously with something flat; whack.


a sharp blow with something flat.

Nearby words

  1. thusly,
  2. thutmose i,
  3. thutmose ii,
  4. thutmose iii,
  5. thuya,
  6. thwaite,
  7. thwart,
  8. thwing,
  9. thwing, charles franklin,
  10. thx

Origin of thwack

First recorded in 1520–30; imitative

Related formsthwack·er, nounout·thwack, verb (used with object)un·thwacked, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for thwack

British Dictionary definitions for thwack



to beat, hit, or flog, esp with something flat


  1. a blow with something flat
  2. the sound made by it


an exclamation imitative of this sound
Derived Formsthwacker, noun

Word Origin for thwack

C16: of imitative origin

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

Word Origin and History for thwack



"to hit hard with a stick," 1520s, of echoic origin. Related: Thwacked; thwacking. The noun is recorded from 1580s.

Online Etymology Dictionary, © 2010 Douglas Harper