Bip39-Mnemonic Code Some words are shorter than four letters, such as the word “act”. Other words are lengthier than four letters, like “abstract”. One particular list of mnemonic can be utilized to generate many addresses. This process of creating account was launched in BIP32 & BIP39 very long time ago. https://bookmarkshq.com/story20036969/bip39-xmr-not-known-factual-statements-about-bip39-word-list