WordNet (r) 3.0 (2006):

unknowing
    adj 1: unaware because of a lack of relevant information or
           knowledge; "he was completely ignorant of the
           circumstances"; "an unknowledgeable assistant"; "his
           rudeness was unwitting" [syn: ignorant,
           unknowledgeable, unknowing, unwitting]
    n 1: ignorance (especially of orthodox beliefs) [syn:
         ignorantness, nescience, unknowing, unknowingness]

Moby Thesaurus II by Grady Ward, 1.0:

67 Moby Thesaurus words for "unknowing":
   a stranger to, asleep, awkward, blankminded, blind to, callow,
   caught napping, dead to, deaf to, dumb, empty, empty-headed,
   gauche, green, groping, ignorant, impercipient, in ignorance of,
   inane, incognizant, inexperienced, innocent, insensible,
   insensible to, know-nothing, mindless, naive, napping, nescient,
   nonconceiving, not with it, out of it, raw, simple, strange to,
   tentative, unacquainted, unapprized, unaware, unaware of,
   uncomprehending, unconscious, unconscious of, unconversant,
   unenlightened, unfamiliar, unhearing, unilluminated, uninformed,
   uninitiated, uninsightful, uninstructed, unintelligent, unmindful,
   unmindful of, unperceiving, unposted, unprehensive, unrealizing,
   unripe, unseeing, unsure, unsuspecting, unversed, unwitting,
   vacuous, witless