Decipherment

from WordNet (r) 3.0 (2006)

decipherment
    n 1: the activity of making clear or converting from code into
         plain text; "a secret key or password is required for
         decryption" [syn: {decoding}, {decryption}, {decipherment}]

from The Collaborative International Dictionary of English v.0.48

Decipherment \De*ci"pher*ment\, n.
   The act of deciphering.
   [1913 Webster]