Kristine Hoover in Discover Magazine:
Have you ever said “I hate you” to someone? What about using the “h-word” in casual conversation, like “I hate broccoli”? What are you really feeling when you say that you hate something or someone?
The Merriam-Webster dictionary describes the word “hate” as an “intense hostility and aversion usually deriving from fear, anger, or sense of injury.” All over the world, researchers like us are studying hate from disciplines like education, history, law, leadership, psychology, sociology and many others.
If you had a scary experience with thunderstorms, you might say that you hate thunderstorms. Maybe you have gotten very angry at something that happened at a particular place, so now you say you hate going there. Maybe someone said something hurtful to you, so you say you hate that person.
More here.