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

unlucky \unluck"y\, a.
   1. not lucky; not successful; unfortunate; ill-fated;
      unhappy; as, an unlucky man; an unlucky adventure; an
      unlucky throw of dice; an unlucky game.
      1913 webster

   note: this word is properly applied to incidents in which
         failure results from chance or fortuity, as in games of
         hazard, rather than from lack or feebleness of effort.
         1913 webster

   2. bringing bad luck; ill-omened; inauspicious.
      1913 webster

            haunt me not with that unlucky face.  --dryden.
      1913 webster

   3. mischievous; as, an unlucky wag. colloq.
      1913 webster

[2] : WordNet (r) 2.0

unlucky
     adj 1: having or bringing misfortune; "friday the 13th is an
            unlucky date" syn: luckless ant: lucky
     2: marked by or promising bad fortune; "their business venture
        was doomed from the start"; "an ill-fated business
        venture"; "an ill-starred romance"; "the unlucky prisoner
        was again put in irons"- w.h.prescott syn: doomed, ill-fated,
         ill-omened, ill-starred
see also:
luckless lucky doomed ill-fated ill-omened ill-starred 

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

94 moby thesaurus words for "unlucky":
   apocalyptic, bad, badly off, baleful, baneful, black, bodeful,
   boding, calamitous, cataclysmic, catastrophic, dark, depressed,
   dire, direful, disastrous, donsie, doomful, dreary, evil,
   evil-starred, fatal, fateful, foreboding, fortuneless, funest,
   gloomy, hapless, ill, ill off, ill-boding, ill-considered,
   ill-fated, ill-omened, ill-seasoned, ill-starred, ill-timed,
   improper, in adverse circumstances, inappropriate, inauspicious,
   inconvenient, inexpedient, infelicitous, inopportune, intempestive,
   intrusive, irrelevant, late, lowering, luckless, mal a propos,
   malapropos, menacing, mistimed, of evil portent, off base, ominous,
   out of line, out of luck, out of phase, out of time, planet-struck,
   portending, portentous, premature, sad, short of luck, sinister,
   somber, star-crossed, threatening, too late, too soon, unbefitting,
   unblessed, underprivileged, unfavorable, unfit, unfitting,
   unfortunate, unhandy, unhappy, unpromising, unpropitious,
   unprosperous, unprovidential, unready, unripe, unseasonable,
   unsuitable, untimely, untoward, wrong

Unlucky >> U Words
Unlucky, definition of term: Unlucky
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