[1] : The Collaborative International Dictionary of English v.0.48

wrench \wrench\, v. t. imp.  p. p. wrenched; p. pr.  vb. n.
   wrenching. oe. wrenchen, as. wrencan to deceive,
   properly, to twist, from wrenc guile, deceit, a twisting.
   ????. see wrench, n.
   1913 webster
   1. to pull with a twist; to wrest, twist, or force by
      violence.
      1913 webster

            wrench his sword from him.            --shak.
      1913 webster

            forthwith this frame of mine was wrenched
            with a woeful agony.                  --coleridge.
      1913 webster

   2. to strain; to sprain; hence, to distort; to pervert.
      1913 webster

            you wrenched your foot against a stone. --swift.
      1913 webster
see also:
wrenched wrenching wrench 

[2] : WordNet (r) 2.0

wrenching
     adj : causing great physical or mental suffering; "a wrenching
           pain" syn: racking
see also:
racking 

Wrenching >> W Words
Wrenching, definition of term: Wrenching
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