I was on bluesky about to comment on some art someone made and was going to comment it is a diamond in the rough but I did a search to make sure it was rough and not ruff because it is not an expression I use much. When I searched it I found out it meant. “a person who is generally of good character but lacks manners, education, or style; a rough diamond.” I just thought it meant hidden gem. Has anyone else misunderstood the meaning of an expression?