Bip39 Passphrase. The passphrase isn't chosen from the predefined list of 2048 words – it could be any word or phrase you choose. explain to your wallet how to find your coins guiding it throughout the tree and are explained in Bitcoin Enhancement Proposals (BIP). BIP-32 hierarchical deterministic wallet. BIP-39 https://getidealist.com/story21250165/bip39-passphrase-https-linktr-ee-bip39-top-guidelines-of-bip39-passphrase