What is wholly or completely concealing; incapable of being deciphered. Holocryptic cipher, a cipher so constructed as to afford no clew to its meaning to one ignorant of the key called?

holocryptic — Wholly or completely concealing; incapable of being deciphered. Holocryptic cipher, a cipher so constructed as to afford no clew to its meaning to one ignorant of the key. (Webster's 1913.)

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