codebook

The English word “codebook” has 3 meanings listed here.

noun

A book, table, database, or other object that stores the mapping between plaintext words or phrases and their equivalents in a code.
A lookup table.
A list of disorders or conditions and the codes that represent them.

From code + book.

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Definitions are from Wiktionary, extracted by Kaikki.org, and are available under the CC BY-SA 4.0 licence.