A person who is appointed, authorized, delegated, or commissioned to act in the place of another. Transfer of authority from one to another. A person to whom affairs are committed by another.
A person elected or appointed to be a member of a representative assembly. Usually spoken of one sent to a special or occasional assembly or convention. Person selected by a constituency and authorized to act for it at a party or state political convention.
As a verb, it means to transfer authority from one person to another; to empower one to perform a task in behalf of another, e.g., a landlord may delegate an agent to collect rents.