Definition - What does Spear Phishing mean?
Spear phishing is a variation on phishing in which hackers send emails to groups of people with specific common characteristics or other identifiers. Spear phishing emails appear to come from a trusted source but are designed to help hackers obtain trade secrets or other classified information.
Techopedia explains Spear Phishing
The difference between spear phishing and a general phishing attempt is subtle. A regular phishing attempt appears to come from a large financial institution or social networking site. It works because, by definition, a large percentage of the population has an account with a company with huge market share.
In spear phishing, an email appears to come from an organization that is closer to the target, such as a particular company. The hacker's goal is to gain access to trusted information. This is often as simple as looking up the name of a CEO from a corporate website and then sending what appears to be a message from the boss to email accounts on the corporate domain.