ADJECTIVE (3)

1. characterized by lack of decision and firmness;
- Example: "an indecisive manager brought the enterprise to a standstill"

2. not definitely settling something;
- Example: "a long and indecisive war"

3. not clearly defined;
- Example: "indecisive boundaries running through mountains"

The Collaborative International Dictionary of English v.0.48:

Indecisive \In`de*ci"sive\, a. [Cf. F. ind['e]cisif.]
   [1913 Webster]
   1. Not decisive; not bringing to a final or ultimate issue;
      as, an indecisive battle, argument, answer.
      [1913 Webster]

            The campaign had everywhere been indecisive.
                                                  --Macaulay.
      [1913 Webster]

   2. Undetermined; prone to indecision; irresolute; unsettled;
      wavering; vacillating; hesitating; as, an indecisive state
      of mind; an indecisive character.
      [1913 Webster]

WordNet (r) 3.0 (2006):

indecisive
    adj 1: characterized by lack of decision and firmness; "an
           indecisive manager brought the enterprise to a
           standstill" [ant: decisive]
    2: not definitely settling something; "a long and indecisive
       war" [ant: decisive]
    3: not clearly defined; "indecisive boundaries running through
       mountains"

Moby Thesaurus II by Grady Ward, 1.0:

214 Moby Thesaurus words for "indecisive":
   adrift, afloat, agnostic, aleatoric, aleatory, alternating,
   ambiguous, ambitendent, ambivalent, amorphic, amorphous, anarchic,
   at loose ends, baggy, bland, blobby, blurred, blurry, borderline,
   broad, capricious, chance, chancy, changeable, changeful, chaotic,
   characterless, confused, desultory, deviable, dicey, disordered,
   disorderly, dizzy, double-minded, doubtful, doubting, dubious,
   eccentric, equivocal, erratic, faltering, fast and loose,
   featureless, fence-sitting, fence-straddling, fickle, fitful,
   flickering, flighty, flitting, fluctuating, foggy, formless,
   freakish, fuzzy, general, giddy, groundless, halfhearted, halting,
   hazy, hesitant, hesitating, hit-or-miss, ill-defined, impetuous,
   imprecise, impulsive, inaccurate, incalculable, inchoate,
   incoherent, inconclusive, inconsistent, inconstant, indefinable,
   indefinite, indemonstrable, indeterminable, indeterminate,
   indistinct, inexact, infirm, infirm of purpose, infirm of will,
   inform, insipid, irregular, irresolute, irresolved, irresponsible,
   kaleidoscopic, lax, loose, lumpen, mazy, mercurial, milk-and-water,
   milky, misty, moody, moot, mugwumpian, mugwumpish, mushy, mutable,
   namby-pamby, neutral, nondescript, nonspecific, not following,
   not proved, obscure, of two minds, open, orderless, polysemous,
   problematic, rambling, random, restless, roving, scatterbrained,
   shadowed forth, shadowy, shaky, shapeless, shifting, shifty,
   shilly-shallying, shuffling, skeptical, spasmodic, spineless,
   stochastic, sweeping, tasteless, tentative, tergiversating,
   touch-and-go, unaccountable, unascertained, unattested,
   unauthenticated, uncertain, uncertified, unclear, unconfirmable,
   unconfirmed, uncontrolled, unconvinced, uncorroborated, undecided,
   undefined, undemonstrated, undependable, undestined, undetermined,
   undisciplined, undivinable, unestablished, unfixed, unforeseeable,
   unfounded, unordered, unorganized, unpersuaded, unplain,
   unpredictable, unprovable, unproved, unproven, unreliable,
   unresolved, unrestrained, unsettled, unshown, unspecified,
   unstable, unstable as water, unstaid, unsteadfast, unsteady,
   unsubstantiated, unsupported, unsupported by evidence, unsure,
   unsustained, untested, untried, unvalidated, unverifiable,
   unverified, vacillating, vagrant, vague, vapid, variable, veiled,
   vicissitudinary, vicissitudinous, volatile, wandering, wanton,
   watery, wavering, wavery, wavy, wayward, whimsical, wishy-washy,
   without basis, without grounds