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

screwing \screw"ing\,
   a.  n. from screw, v. t.
   1913 webster

   screwing machine. see screw machine, under screw.
      1913 webster
see also:
screw screwing machine screw machine 

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

screw \screw\ skrudd, v. t. imp.  p. p. screwed
   skruddd; p. pr.  vb. n. screwing.
   1. to turn, as a screw; to apply a screw to; to press,
      fasten, or make firm, by means of a screw or screws; as,
      to screw a lock on a door; to screw a press.
      1913 webster

   2. to force; to squeeze; to press, as by screws.
      1913 webster

            but screw your courage to the sticking place,
            and we'll not fail.                   --shak.
      1913 webster

   3. hence: to practice extortion upon; to oppress by
      unreasonable or extortionate exactions.
      1913 webster

            our country landlords, by unmeasurable screwing and
            racking their tenants, have already reduced the
            miserable people to a worse condition than the
            peasants in france.                   --swift.
      1913 webster

   4. to twist; to distort; as, to screw his visage.
      1913 webster

            he screwed his face into a hardened smile. --dryden.
      1913 webster

   5. to examine rigidly, as a student; to subject to a severe
      examination. cant, american colleges
      1913 webster

   to screw out, to press out; to extort.

   to screw up,
      a to force; to bring by violent pressure. --howell.
      b to damage by unskillful effort; to bungle; to botch;
          to mess up; as, he screwed up the contract
          negotiations, and we lost the deal.
      c intrans. to fail by unskillful effort, usually
          causing unpleasant consequences.

   to screw in, to force in by turning or twisting.

   screw around,
      a to act aimlessly or unproductively.
      b to commit adultery; to be sexually promiscuous.

   screw around with, to operate or make changes on a machine
      or device without expert knowledge; to fiddle with.
      colloq. . -->
      1913 webster
see also:
screwed screwing to screw out to screw up to screw in screw around 
screw around with 

[3] : WordNet (r) 2.0

screwing
     n : slang terms for sexual intercourse syn: fuck, fucking,
         screw, ass, nooky, nookie, piece of ass, piece
         of tail, roll in the hay, shag, shtup
see also:
fuck fucking screw ass nooky nookie 
piece of ass piece of tail roll in the hay shag shtup 

Screwing >> S Words
Screwing, definition of term: Screwing
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