You know what it looks like… but what is it called?
TAKE THE QUIZ“part code”
The following 2 entries include the term part code.
one-part code
noun: a code having code groups assigned in alphabetical or numerical order to an alphabetically and logically arranged list of plaintext segments compare two-part code
two-part code
noun: a codebook having an encoding part listing the plaintext segments in alphabetical and logical order each with its code group or groups assigned at random and a decoding part listing in alphabetical or numerical order the code groups with their plaintext equivalents compare one-part code