The Rice University Neologisms Database

Spam or fraudulent emails that suggest great rewards and prizes for signing up, but only exist to scam people out of money. Although the practice of phishing, and the name, have been around for a while, there was never any word to describe the frauds and emails themselves. Usually they would just be referred to as email frauds, or fraudulent spam. It only makes sense that ‘phishing’ would be cut down into a noun form in order to create that word. If this entire practice was paralleled to fishing as the first word was, the emails and offers would be considered the bait and hook, while the people were considered the phish, which shows that the word phish was not formed by this metaphor, but rather by the back formation of the already established phishing practice.