What Is a Whaling Attack?
A whaling attack is a type of phishing attack where a particularly important person in the organization is targeted. It hinges on the cyber criminal pretending to be a senior member of the organization to gain the trust of the intended target. Once trust is gained, the attacker can prod the target for information that helps them access sensitive areas of the network, passwords, or other user account information.
https://www.fortinet.com/resources/cyberglossary/whaling-attack