D defs.my
Entry 1 sense Webster, 1913

Holocryptic

· Hol·o·cryp·tic · IPA /ˌhɑ.ləˈkɹɪp.tɪk/
01 a. Wholly or completely concealing; incapable of being deciphered.
  1. 1.
    Wholly or completely concealing; incapable of being deciphered.
Phrases & compounds
Holocryptic cipher — a cipher so constructed as to afford no clew to its meaning to one ignorant of the key.