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

sicken \sick"en\, v. t. imp.  p. p. sickened; p. pr.  vb.
   n. sickening.
   1. to make sick; to disease.
      1913 webster

            raise this strength, and sicken that to death.
                                                  --prior.
      1913 webster

   2. to make qualmish; to nauseate; to disgust; as, to sicken
      the stomach.
      1913 webster

   3. to impair; to weaken. obs. --shak.
      1913 webster
see also:
sickened sickening 

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

sicken \sick"en\, v. i.
   1. to become sick; to fall into disease.
      1913 webster

            the judges that sat upon the jail, and those that
            attended, sickened upon it and died.  --bacon.
      1913 webster

   2. to be filled to disgust; to be disgusted or nauseated; to
      be filled with abhorrence or aversion; to be surfeited or
      satiated.
      1913 webster

            mine eyes did sicken at the sight.    --shak.
      1913 webster

   3. to become disgusting or tedious.
      1913 webster

            the toiling pleasure sickens into pain. --goldsmith.
      1913 webster

   4. to become weak; to decay; to languish.
      1913 webster

            all pleasures sicken, and all glories sink. --pope.
      1913 webster

[3] : WordNet (r) 2.0

sicken
     v 1: cause aversion in; offend the moral sense of; "the
          pornographic pictures sickened us" syn: disgust, revolt,
           nauseate, churn up
     2: get sick; "she fell sick last friday, and now she is in the
        hospital" syn: come down
     3: upset and make nauseated; "the smell of the foood turned the
        pregnant woman's stomach"; "the mold ont he food sickened
        the diners" syn: nauseate, turn one's stomach
     4: make sick or ill; "this kind of food sickens me"
see also:
disgust revolt nauseate churn up come down turn one's stomach 

[4] : Moby Thesaurus II by Grady Ward, 1.0

69 moby thesaurus words for "sicken":
   od, affect, afflict, appall, be brought down, be felled,
   be struck down, be traumatized, break out, catch, catch cold,
   collapse, come down with, contract, debilitate, degenerate,
   derange, deteriorate, devitalize, disable, disgust, disimprove,
   disorder, enervate, enfeeble, erupt, fail, fall back, fever, get,
   get worse, give offense, go into shock, gross out, grow worse,
   horrify, hospitalize, incapacitate, indispose, invalid, lay up,
   let down, nauseate, offend, overdose, put off, put out, reduce,
   regress, relapse, reluct, repel, repulse, retrograde, retrogress,
   revolt, run a temperature, shock, slacken, slip back, take,
   take ill, turn, turn the stomach, unhinge, unsettle, upset, weaken,
   worsen

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