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

decease \decease"\, n. oe. deses, deces, f. d'ec`es, fr.
   l. decessus departure, death, fr. decedere to depart, die;
   de- + cedere to withdraw. see cease, cede.
   departure, especially departure from this life; death.
   1913 webster

         his decease, which he should accomplish at jerusalem.
                                                  --luke ix. 31.
   1913 webster

         and i, the whilst you mourn for his decease,
         will with my mourning plaints your plaint increase.
                                                  --spenser.

   syn: death; departure; dissolution; demise; release. see
        death.
        1913 webster
see also:
cease cede death 

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

decease \decease"\, v. i. imp.  p. p. deceased; p. pr. 
   vb. n. deceasing.
   to depart from this life; to die; to pass away.
   1913 webster

         she's dead, deceased, she's dead.        --shak.
   1913 webster

         when our summers have deceased.          --tennyson.
   1913 webster

         inasmuch as he carries the malignity and the lie with
         him, he so far deceases from nature.     --emerson.
   1913 webster
see also:
deceased deceasing 

[3] : WordNet (r) 2.0

decease
     n : the event of dying or departure from life; "her death came
         as a terrible shock"; "upon your decease the capital will
         pass to your grandchildren" syn: death ant: birth
     v : pass from physical life and lose all all bodily attributes
         and functions necessary to sustain life; "she died from
         cancer"; "they children perished in the fire"; "the
         patient went peacefully" syn: die, perish, go, exit,
          pass away, expire, pass ant: be born
see also:
death birth die perish go exit 
pass away expire pass be born 

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

132 moby thesaurus words for "decease":
   z, annihilation, apodosis, bane, be lost, biological death,
   cash in, catastrophe, cease to be, cease to live, ceasing,
   cessation, cessation of life, clinical death, coda, conclusion,
   consummation, crack of doom, crossing the bar, culmination,
   curtain, curtains, death, death knell, debt of nature, demise,
   denouement, depart, depart this life, departure, destination,
   destiny, die, dissolution, doom, drop, dying, ebb of life, effect,
   end, end of life, end point, ending, envoi, epilogue, eschatology,
   eternal rest, exit, expiration, expire, extinction, extinguishment,
   fall, fall asleep, fate, final solution, final summons,
   final twitch, final words, finale, finality, finger of death,
   finis, finish, go, go out, goal, going, going off, grave,
   hand of death, izzard, jaws of death, knell, last, last breath,
   last debt, last gasp, last muster, last rest, last roundup,
   last sleep, last things, last trumpet, last words, latter end,
   leaving life, loss of life, making an end, omega, part, parting,
   pass, pass away, pass on, pass over, passing, passing away,
   passing over, payoff, period, perish, perishing, peroration,
   put off mortality, quietus, quit this world, release, resolution,
   rest, resting place, return to dust, reward, sentence of death,
   shades of death, shadow of death, silence, sleep, somatic death,
   stop breathing, stoppage, stopping place, succumb,
   summons of death, swan song, term, terminal, termination, terminus,
   up and die, windup, yield the ghost

Decease >> D Words
Decease, definition of term: Decease
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