The Collaborative International Dictionary of English v.0.48:

Recondite \Rec"on*dite\ (r[e^]k"[o^]n*d[imac]t or
   r[-e]k[o^]n"d[i^]t; 277), a. [L. reconditus, p. p. of
   recondere to put up again, to lay up, to conceal; pref. re-
   re- + condere to bring or lay together. See Abscond.]
   1. Hidden from the mental or intellectual view; secret;
      abstruse; as, recondite causes of things.
      [1913 Webster]

   2. Dealing in things abstruse; profound; searching; as,
      recondite studies. "Recondite learning." --Bp. Horsley.
      [1913 Webster]

WordNet (r) 3.0 (2006):

recondite
    adj 1: difficult to penetrate; incomprehensible to one of
           ordinary understanding or knowledge; "the professor's
           lectures were so abstruse that students tended to avoid
           them"; "a deep metaphysical theory"; "some recondite
           problem in historiography" [syn: abstruse, deep,
           recondite]

Moby Thesaurus II by Grady Ward, 1.0:

79 Moby Thesaurus words for "recondite":
   abstract, abstruse, academic, arcane, beclouded, blind, buried,
   cabalistic, cabbalistic, close, clouded, concealed, covered,
   covert, cryptic, dark, deep, difficult, do up, doctor, eclipsed,
   enigmatic, erudite, esoteric, hard, heavy, hermetic, hid, hidden,
   impenetrable, in a cloud, in a fog, in eclipse, in purdah,
   in the wings, incommunicado, incomprehensible, inexplicable,
   latent, learned, mysterious, mystic, mystical, obfuscated, obscure,
   obscured, occult, opaque, overhaul, patch, pedantic, profound,
   rebuild, reclaim, recondition, reconstruct, recover, rehabilitate,
   rejuvenate, repair, restitute, revamp, runic, scholarly, secluded,
   secluse, secret, sequestered, sibylline, transcendental,
   undecipherable, under an eclipse, under cover, under house arrest,
   under wraps, underground, unfathomable, unknown,
   wrapped in clouds