When you say that you are the cat’s whiskers, what you are suggesting is that you are better than those around you. You are the most outstanding. In other words, the others are beneath you.
Examples: Many of the people who work in government offices think they are the cat’s whiskers. * Cinderella probably thought that she was the cat’s whiskers in her new dress. * Many of our film stars think that they are the cat’s whiskers.