Noun - When a person falls in love with someone in an obsessive, psychotic manner, then proceeds to have sex with them, and when they are denied a relationship, in a blind rage of fury, they kill the person.
Guy 1) Did you read the papertoday? This guy had one reeeeally psychotic obsession for this chick. Sad story.
Guy 2) I read that! He should be put away for life. The sickest lovefuckmurder i've ever heard.
Guy 1) I know! He kept whining to her that he loved her so much so they finally had sex so he'd stop bugging her, but when he asked her out for the millionth time afterwards and she said no he caved her skull in with a louisville slugger!
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).