The Collaborative International Dictionary of English v.0.48:

Haphazard \Hap"haz`ard\ (h[a^]p"h[a^]z`[~e]rd or
   h[a^]p`h[a^]z"[~e]rd), n. [Hap + hazard.]
   Extra hazard; chance; accident; random.
   [1913 Webster]

         We take our principles at haphazard, upon trust.
                                                  --Locke.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

haphazard \hap"haz`ard\ (h[a^]p"h[a^]z`[~e]rd or
   h[a^]p`h[a^]z"[~e]rd), a.
   Determined by chance, whimsy, or guesswork; unplanned;
   aimless; random; -- used mostly of human actions.
   [PJC]

WordNet (r) 3.0 (2006):

haphazard
    adv 1: without care; in a slapdash manner; "the Prime Minister
           was wearing a grey suit and a white shirt with a soft
           collar, but his neck had become thinner and the collar
           stood away from it as if it had been bought haphazard"
           [syn: haphazard, haphazardly]
    adj 1: dependent upon or characterized by chance; "a haphazard
           plan of action"; "his judgment is rather hit-or-miss"
           [syn: haphazard, hit-or-miss]
    2: marked by great carelessness; "a most haphazard system of
       record keeping"; "slapdash work"; "slipshod spelling";
       "sloppy workmanship" [syn: haphazard, slapdash,
       slipshod, sloppy]

Moby Thesaurus II by Grady Ward, 1.0:

125 Moby Thesaurus words for "haphazard":
   accidental, accidentally, ad-lib, aimless, aimlessly, amorphous,
   any which way, anyhow, anywise, around, at random, botched,
   bungling, capricious, careless, carelessly, casual, casually,
   caught napping, caught off balance, caught short, causeless,
   chance-medley, clumsy, deficient, designless, desultory,
   disarticulated, discontinuous, disjunct, disordered, dispersed,
   disproportionate, driftless, dysteleological, erratic,
   extemporaneous, extemporized, fitful, formless, frivolous,
   gratuitous, half-assed, haphazardly, hasty, helter-skelter,
   hit-and-miss, hit-or-miss, immethodical, impromptu, improvised,
   inchoate, incoherent, indiscriminate, inexplicable, irregular,
   makeshift, meaningless, messy, mindless, misshapen, nonsymmetrical,
   nonsystematic, nonuniform, orderless, planless, potluck,
   precipitate, promiscuous, promiscuously, purposeless, random,
   random shot, randomly, rough-and-ready, senseless, shapeless,
   slipshod, slipshoddy, sloppy, slovenly, sluttish, snap, spasmodic,
   sporadic, stochastic, straggling, straggly, systemless,
   taken aback, taken by surprise, taken unawares, tripped up,
   unaccountable, unarranged, unbegun, unclassified, unconcocted,
   unconsidered, uncontrived, undeliberated, undevised, undirected,
   ungraded, unhatched, unjoined, unmade, unmanufactured,
   unmethodical, unmotivated, unordered, unorganized, unplanned,
   unpremeditated, unprepared, unprimed, unready, unsorted, unstudied,
   unsymmetrical, unsystematic, untidy, ununiform, vague, wandering