The Collaborative International Dictionary of English v.0.48:

Unconditioned \Un`con*di"tioned\, a.
   1. Not conditioned or subject to conditions; unconditional.
      [1913 Webster]

   2. (Metaph.) Not subject to conditions or limitations;
      infinite; absolute; hence, inconceivable; incogitable.
      --Sir W. Hamilton.
      [1913 Webster]

   The unconditioned (Metaph.), all that which is
      inconceivable and beyond the realm of reason; whatever is
      inconceivable under logical forms or relations.
      [1913 Webster]

WordNet (r) 3.0 (2006):

unconditioned
    adj 1: not established by conditioning or learning; "an
           unconditioned reflex" [syn: unconditioned, innate,
           unlearned] [ant: conditioned, learned]
    2: not conditional; "unconditional surrender" [syn:
       unconditional, unconditioned] [ant: conditional]