The word maleficent means causing harm especially by supernatural means, and we can determine this because the root 'mal' means evil as stated, and maleficent is a term used for evil occurences (specifically in movies and stuff)
Explanation:
So you can determine that the adjective describes something evil or bad because of the use of the root :) Sorry if this isn't specific enough, but it's quite straight forward to me at least so I don't know how to elaborate if you need a more formal answer