A person (or a business like a bank or stock brokerage) who has the power and obligation to act for another (often called the beneficiary) under circumstances that require total trust, good faith and honesty.
Fiduciary Duty
A duty to act for someone else’s benefit, while subordinating one’s personal interests to that of the other person. It is the highest standard of duty implied by law (e.g., trustee, guardian) assigned here.