A custom dictionary that filters out certain words that are not allowed as passwords in the environment can significantly improve cybersecurity posture and filter out obvious passwords that provide poor security for user accounts. The custom dictionary works in favor of securing the passwords in your environment. There are out-of-the-box password dictionaries and password files that can be freely downloaded as the basis for a custom password dictionary for your password policy. Organizations that create their own custom password filter are more involved than creating their own.
Source: https://thehackernews.com/2021/07/crafting-custom-dictionary-for-your.html