- to strike or beat vigorously with something flat; whack.
- a sharp blow with something flat.
Origin of thwack
First recorded in 1520–30; imitative
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for thwack
Geddie leaped high and caught the roll with a sounding "thwack."Cabbages and Kings</p>
His wife, taken aback, started up and gave him a thwack on the back.Pelle the Conqueror, Complete
Martin Anderson Nexo
She struck one plank a thwack with the small axe she carried in her hand.Green Eyes
Roy J. Snell
Then, above the murmur from the temple, he heard a sound in the corridor—a thwack.Caravans By Night
Jock's hand came down with a thwack on the papers before him.Personality Plus
- to beat, hit, or flog, esp with something flat
- a blow with something flat
- the sound made by it
- an exclamation imitative of this sound
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