The Collaborative International Dictionary of English v.0.48:

Sick \Sick\, n.
   Sickness. [Obs.] --Chaucer.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sick \Sick\, v. i.
   To fall sick; to sicken. [Obs.] --Shak.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sick \Sick\, a. [Compar. Sicker; superl. Sickest.] [OE. sek,
   sik, ill, AS. se['o]c; akin to OS. siok, seoc, OFries. siak,
   D. ziek, G. siech, OHG. sioh, Icel. sj?kr, Sw. sjuk, Dan.
   syg, Goth. siuks ill, siukan to be ill.]
   1. Affected with disease of any kind; ill; indisposed; not in
      health. See the Synonym under Illness.
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            Simon's wife's mother lay sick of a fever. --Mark i.
                                                  30.
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            Behold them that are sick with famine. --Jer. xiv.
                                                  18.
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   2. Affected with, or attended by, nausea; inclined to vomit;
      as, sick at the stomach; a sick headache.
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   3. Having a strong dislike; disgusted; surfeited; -- with of;
      as, to be sick of flattery.
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            He was not so sick of his master as of his work.
                                                  --L'Estrange.
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   4. Corrupted; imperfect; impaired; weakned.
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            So great is his antipathy against episcopacy, that,
            if a seraphim himself should be a bishop, he would
            either find or make some sick feathers in his wings.
                                                  --Fuller.
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   Sick bay (Naut.), an apartment in a vessel, used as the
      ship's hospital.

   Sick bed, the bed upon which a person lies sick.

   Sick berth, an apartment for the sick in a ship of war.

   Sick headache (Med.), a variety of headache attended with
      disorder of the stomach and nausea.

   Sick list, a list containing the names of the sick.

   Sick room, a room in which a person lies sick, or to which
      he is confined by sickness.

   Note: [These terms, sick bed, sick berth, etc., are also
         written both hyphened and solid.]
         [1913 Webster]

   Syn: Diseased; ill; disordered; distempered; indisposed;
        weak; ailing; feeble; morbid.
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WordNet (r) 3.0 (2006):

sick
    adj 1: affected by an impairment of normal physical or mental
           function; "ill from the monotony of his suffering" [syn:
           ill, sick] [ant: well]
    2: feeling nausea; feeling about to vomit [syn: nauseated,
       nauseous, queasy, sick, sickish]
    3: affected with madness or insanity; "a man who had gone mad"
       [syn: brainsick, crazy, demented, disturbed, mad,
       sick, unbalanced, unhinged]
    4: having a strong distaste from surfeit; "grew more and more
       disgusted"; "fed up with their complaints"; "sick of it all";
       "sick to death of flattery"; "gossip that makes one sick";
       "tired of the noise and smoke" [syn: disgusted, fed
       up(p), sick(p), sick of(p), tired of(p)]
    5: (of light) lacking in intensity or brightness; dim or feeble;
       "the pale light of a half moon"; "a pale sun"; "the late
       afternoon light coming through the el tracks fell in pale
       oblongs on the street"; "a pallid sky"; "the pale (or wan)
       stars"; "the wan light of dawn" [syn: pale, pallid,
       wan, sick]
    6: deeply affected by a strong feeling; "sat completely still,
       sick with envy"; "she was sick with longing"
    7: shockingly repellent; inspiring horror; "ghastly wounds";
       "the grim aftermath of the bombing"; "the grim task of
       burying the victims"; "a grisly murder"; "gruesome evidence
       of human sacrifice"; "macabre tales of war and plague in the
       Middle ages"; "macabre tortures conceived by madmen" [syn:
       ghastly, grim, grisly, gruesome, macabre, sick]
    n 1: people who are sick; "they devote their lives to caring for
         the sick"
    v 1: eject the contents of the stomach through the mouth; "After
         drinking too much, the students vomited"; "He purged
         continuously"; "The patient regurgitated the food we gave
         him last night" [syn: vomit, vomit up, purge, cast,
         sick, cat, be sick, disgorge, regorge, retch,
         puke, barf, spew, spue, chuck, upchuck, honk,
         regurgitate, throw up] [ant: keep down]