Bip39 Passphrase. As the 24th is really a checksum word, a list of eight valid applicant words are calculated using the Python script 24thword.py. Along with its unique composition, it have to use a selected list of words when making your mnemonic phrase. That is known as the BIP39 wordlist. https://ontopicdirectory.com/listings13040157/bip39-word-list-numbers-https-linktr-ee-bip39-not-known-facts-about-bip39-mnemonic-generator