BIP39 means Bitcoin Enhancement Proposal 39. The words are selected from a certain list of 2048 common English words which may be used to the deliver a binary seed (your private critical). Standard recovery phrases use a specific list of 2048 words subsequent the BIP39 standard (Bitcoin Enhancement Proposal 39). https://fellowfavorite.com/story19964364/the-fact-about-bip39-seed-phrase-word-list-that-no-one-is-suggesting