Jekyll and Hyde/ˈʤɛkələnˈhaɪd/noun
Learner's definition of JEKYLL AND HYDE
: someone who is sometimes good and pleasant and sometimes very rude or bad
◊ This term comes from “The Strange Case of Dr. Jekyll and Mr. Hyde,” a story by Robert Louis Stevenson. In the story, Dr. Jekyll is a scientist who creates a liquid that changes him from a good man to the evil Mr. Hyde when he drinks it.