superencipherment
/ˌs(j)uːpərˌɪnˈsʌɪfəm(ə)nt/ /ˌs(j)uːpərˌɛnˈsʌɪfəm(ə)nt/(also superencypherment)
noun
The action or process of recoding a message that is already enciphered. Also: an instance or the result of this; a message or code that has been superenciphered.
Origin
1940s. From super- + encipher + -ment. Compare later superencipher.