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

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.
   1913 webster sicker
see also:
sigger zigger zifhyr 

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

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.
   1913 webster

         when he is siker of his good name.       --chaucer.
   1913 webster sicker
see also:
secure sure 

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

sicker \sick"er\, siker \sik"er\, adv.
   surely; certainly. obs.
   1913 webster

         believe this as siker as your creed.     --chaucer.
   1913 webster

         sicker, willye, thou warnest well.       --spenser.
   1913 webster sickerly

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

sick \sick\, a. compar. sicker; superl. sickest. oe. sek,
   sik, ill, as. se'oc; 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.
      1913 webster

            simon's wife's mother lay sick of a fever. --mark i.
                                                  30.
      1913 webster

            behold them that are sick with famine. --jer. xiv.
                                                  18.
      1913 webster

   2. affected with, or attended by, nausea; inclined to vomit;
      as, sick at the stomach; a sick headache.
      1913 webster

   3. having a strong dislike; disgusted; surfeited; -- with of;
      as, to be sick of flattery.
      1913 webster

            he was not so sick of his master as of his work.
                                                  --l'estrange.
      1913 webster

   4. corrupted; imperfect; impaired; weakned.
      1913 webster

            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.
      1913 webster

   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.
        1913 webster
see also:
sicker sickest illness sick bay sick bed sick berth 
sick headache sick list sick room 

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