an active and efficient cause; capable of producing a certain effect
"their research uncovered new disease agents"
a representative who acts on behalf of other persons or organizations
"The real estate agent helped us find our dream home by negotiating directly with the sellers."
a substance that exerts some force or effect
"The chemical agent used to clean the spill evaporated quickly, leaving no trace behind."
any agent or representative of a federal agency or bureau
"The security guard asked to see my identification before allowing me into the restricted area, claiming he was an official agent representing the FBI."
the semantic role of the animate entity that instigates or causes the happening denoted by the verb in the clause
"When analyzing the grammar, students learn to identify the agent as the person who actually performs the action described by the verb."
One who exerts power, or has the power to act
"The storm acted as a powerful agent of change, tearing down the old pines and reshaping the valley in just hours."
In plain English: An agent is someone who acts on behalf of another person to handle tasks or make decisions for them.
"The travel agent helped me book a flight to Paris for my vacation."
Usage: In everyday use, an agent is a person authorized to act on behalf of another individual or organization, such as a real estate agent selling a home for its owner. Do not confuse this role with the abstract definition of one who simply exerts power; instead, focus on the specific context of representation and delegation.
A surname.
"Mr. Agent stopped by to collect his mail, though I've never heard anyone use that as a last name before."
The word agent comes from the Latin verb agere, which means to drive or manage. It entered English as a noun describing someone who performs an action or carries out a task.