1. [n]  people who are sick; "they devote their lives to caring for the sick"
2. [adj]  affected with madness or insanity; "a man who had gone mad"
3. [adj]  not in good physical or mental health; "ill from the monotony of his suffering"
4. [adj]  feeling nausea; feeling about to vomit
5. [v]  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"

Sick
Presents a history of the sport and an examination of the lifestyle, attitudes, and passions of its enthusiasts

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1. \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}.
            Simon's wife's mother lay sick of a fever. --Mark i.
                                                  30.
            Behold them that are sick with famine. --Jer. xiv.
                                                  18.
   2. Affected with, or attended by, nausea; inclined to vomit;
      as, sick at the stomach; a sick headache.
   3. Having a strong dislike; disgusted; surfeited; -- with of;
      as, to be sick of flattery.
            He was not so sick of his master as of his work.
                                                  --L'Estrange.
   4. Corrupted; imperfect; impaired; weakned.
            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.
   {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.]
   Syn: Diseased; ill; disordered; distempered; indisposed;
        weak; ailing; feeble; morbid.
   

2. \Sick\, n.
   Sickness. [Obs.] --Chaucer.
   

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