The contents of the word list do not have to be protected or concealed in any way, as the security of a Diceware passphrase is in the number of words selected, ...
Diceware is a method used to generate cryptographically strong passphrases. It is based on the principle that truly random selection of words from a wordlist can result in easily memorable passwords that are also extremely resistant to attack .
Diceware passwords are good enough if they are long enough. If you have a three word diceware password to keep your password database safe, I'd say: no, not ...