Seed Phrase Generator Offline Some words are shorter than 4 letters, like the word “act”. Other words are extended than four letters, for instance “summary”. 1 list of mnemonic can be used to make numerous addresses. This process of building account was introduced in BIP32 & BIP39 very long time https://adsbookmark.com/story18596566/bip39-encoding-little-known-facts-about-bip39-word-list