Source : Webster's Revised Unabridged Dictionary (1913)

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}.

            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.

Sicker \Sick"er\, v. i. [AS. sicerian.] (Mining)
   To percolate, trickle, or ooze, as water through a crack.
   [Also written {sigger}, {zigger}, and {zifhyr}.] [Prov. Eng.]

Sicker \Sick"er\, Siker \Sik"er\, a. [OE. siker; cf. OS. sikur,
   LG. seker, D. zeker, Dan. sikker, OHG. sihhur, G. sicher; all
   fr. L. securus. See {Secure}, {Sure}.]
   Sure; certain; trusty. [Obs. or Prov. Eng. & Scot.] --Burns.

         When he is siker of his good name.       --Chaucer.

Sicker \Sick"er\, Siker \Sik"er\, adv.
   Surely; certainly. [Obs.]

         Believe this as siker as your creed.     --Chaucer.

         Sicker, Willye, thou warnest well.       --Spenser.