Bit 39 Word List BIP 39 defines how to create a human-readable backup on your wallet identified as a mnemonic or seed phrase. Meaning if you have the first four letters, you know the remainder of the word by looking for those 1st four letters while in the BIP39 wordlist. https://rowanqbmok.gynoblog.com/30792734/bitcoin-seed-phrase-generator-bip39-no-further-a-mystery