Source : Webster's Revised Unabridged Dictionary (1913)

Indistinct \In`dis*tinct"\, a. [L. indistinctus: cf. F.
   indistinct. See {In-} not, and {Distinct}.]
   1. Not distinct or distinguishable; not separate in such a
      manner as to be perceptible by itself; as, the indistinct
      parts of a substance. ``Indistinct as water is in water.''
      --Shak.

   2. Obscure to the mind or senses; not clear; not definite;
      confused; imperfect; faint; as, indistinct vision; an
      indistinct sound; an indistinct idea or recollection.

            When we come to parts too small four our senses, our
            ideas of these little bodies become obscure and
            indistinct.                           --I. Watts.

            Their views, indeed, are indistinct and dim.
                                                  --Cowper.

   Syn: Undefined; indistinguishable; obscure; indefinite;
        vague; ambiguous; uncertain; confused.

Source : WordNet®

indistinct
     adj : not clearly defined or easy to perceive or understand;
           "indistinct shapes in the gloom"; "an indistinct
           memory"; "only indistinct notions of what to do" [ant:
           {distinct}]