ENGLISH
REFERENCE

agent

n.
US //ˈeɪdʒənt// UK //ˈeɪdʒənt// agent
  1. 1 business representative (n.)
    B1 Intermediate Law

    a person who acts for another person or business, especially to help them with work or legal matters.

    a person authorized to act for or in place of another, known as the principal, in business or legal transactions.

    Example

    The real estate agent showed us three different houses in the city center.

    Example

    The athlete's agent negotiated a multi-year contract that included significant performance bonuses and image rights clauses.
  2. 2 intelligence or police officer (n.)
    B1 Intermediate

    a person who works for a government's secret service or a specific police department.

    an official employed by a government intelligence agency or a specialized law enforcement department.

    Example

    In the movie, the secret agent had to stop a dangerous criminal.

    Example

    Federal agents conducted a coordinated raid on the warehouse after months of surveillance and undercover work.
Show 3 more sensesShow fewer
  1. 3 active substance (n.)
    B2 Upper Intermediate Technical Science

    a chemical or biological substance that causes a specific effect or change.

    a substance or force that produces a biological, chemical, or physical effect.

    Example

    Soap is a cleaning agent that helps remove grease from your hands.

    Example

    The researchers identified a specific chemical agent in the soil that was preventing the local crops from growing properly.
  2. 4 software process (n.)
    C1 Advanced Technical Computing

    a computer program that acts on your behalf to perform tasks automatically.

    an autonomous or semi-autonomous computer program that performs tasks on behalf of a user or another program.

    Example

    The smart software agent finds the cheapest flights for you automatically.

    Example

    Intelligent agents within the network monitor traffic patterns to optimize data routing and prevent server congestion during peak hours.
  3. 5 grammatical doer (n.)
    C1 Advanced Academic Technical Grammar

    the person or thing in a sentence that performs the action.

    the semantic role of the entity that instigates or performs the action of the verb.

    Example

    In the sentence 'The chef cooked the meal', the chef is the agent.

    Example

    In passive constructions, the agent is often expressed in a prepositional phrase starting with 'by' or is omitted entirely.
Origin

Etymology tree Proto-Indo-European *h₂eǵ- Proto-Indo-European *h₂éǵeti Proto-Italic *agō Latin agō Latin agēnsder. English agent From Latin agēns, present active participle of agere (“to drive, lead, conduct, manage, perform, do”).

Word family

© 2026 English Reference