Bip39 List. The passphrase isn't selected from the predefined list of 2048 words – it might be any word or phrase you end up picking. BIP39 specifies a list of 2048 words from which the mnemonic phrase is preferred. Each individual word signifies a selection inside of a binary sequence, https://thebookpage.com/story4023321/bip39-https-linktr-ee-bip39-5-easy-facts-about-bip39-generator-described