Bip39 Seed. The passphrase is not picked in the predefined list of 2048 words – it might be any word or phrase you select. BIP39 specifies a list of 2048 words from which the mnemonic phrase is decided on. Every single word represents a range in a very binary sequence, https://extrabookmarking.com/story19134628/bip39-generator-https-linktr-ee-bip39-not-known-details-about-bip39-list