For words that have only three letters, there is absolutely no 4th letter. For example with the word “add”, there are no a lot more letters afterwards and thus must be the word "increase". The word “addict” is during the BIP39 wordlist however you would've employed “addi” for “addict”. Unlock https://hotbookmarkings.com/story18832457/a-review-of-bip39-phrase-list