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noun \ˈā-jənt\

Simple Definition of agent

  • : a person who does business for another person : a person who acts on behalf of another

  • : a person who tries to get secret information about another country, government, etc.

  • : a person or thing that causes something to happen

Source: Merriam-Webster's Learner's Dictionary

Full Definition of agent

  1. 1 :  one that acts or exerts power

  2. 2 a :  something that produces or is capable of producing an effect :  an active or efficient cause b :  a chemically, physically, or biologically active principle

  3. 3 :  a means or instrument by which a guiding intelligence achieves a result

  4. 4 :  one who is authorized to act for or in the place of another: as a :  a representative, emissary, or official of a government <crown agent> <federal agent> b :  one engaged in undercover activities (as espionage) :  spy <secret agent> c :  a business representative (as of an athlete or entertainer) <a theatrical agent>

  5. 5 :  a computer application designed to automate certain tasks (as gathering information online)

Examples of agent in a sentence

  1. They worked with a travel agent to plan their vacation.

  2. <the whitening agent in the detergent is chlorine bleach>

Origin of agent

Middle English, from Medieval Latin agent-, agens, from Latin, present participle of agere to drive, lead, act, do; akin to Old Norse aka to travel in a vehicle, Greek agein to drive, lead

First Known Use: 15th century

AGENT Defined for Kids


noun \ˈā-jənt\

Definition of agent for Students

  1. 1 :  something that produces an effect <cleansing agents>

  2. 2 :  a person who acts or does business for another <a travel agent>

Medical Dictionary


noun \ˈā-jənt\

Medical Definition of agent

  1. 1:  something that produces or is capable of producing an effect

  2. 2:  a chemically, physically, or biologically active principle—see oxidizing agent, reducing agent

Law Dictionary



Legal Definition of agent

  1. 1 :  someone or something that acts or exerts power :  a moving force in achieving some result

  2. 2 :  a person guided or instigated by another in some action <where the heads of departments are the political…agents of the executive, merely to execute the will of the president — Marbury v. Madison, 5 U.S. 137 (1803)> — see also innocent agent

  3. 3a :  a person or entity (as an employee or independent contractor) authorized to act on behalf of and under the control of another in dealing with third parties — see also agency 2, fiduciary relationship, subagent — compare fiduciary, principal, servant apparent agent :  an agent acting under an agency by estoppel bargaining agent :  a labor union that represents the employees in a bargaining unit in negotiating with their employer through collective bargaining business agent :  an agent that handles business affairs for another person or organization; especially :  a paid official of a union who carries on union business between the employees and the employer collective bargaining agent :  bargaining agent in this entry del credere agent :  an agent that guarantees to his or her principal that third parties involved in the transaction will pay or performenrolled agent :  a person qualified through expertise and good reputation to represent taxpayers before the Internal Revenue Service exclusive agent :  an agent acting under an exclusive agency general agent :  an agent acting under a general agency legislative agent :  an agent (as for an interest group) that lobbies a legislature especially professionally managing agent :  an agent or employee of a corporation or other business entity who has a position that involves the use of judgment and discretion and who is considered under the law as capable of accepting service of process and answering questions under cross-examination on behalf of the business entity ostensible agent :  an agent acting under an agency by estoppel special agent :  an agent authorized to do one or more specific acts under particular instructions or within restrictions implied by the nature of the authorized acts :  an agent acting under a special agency — compare general agent in this entry transfer agent :  an officer, bank, or trust company that acts on behalf of a publicly held corporation in handling the transfer of stock and other securities and keeping records of the owners universal agent :  an agent acting under a general agency b :  a representative (as of a corporation or nonresident administrator of an estate) designated to accept service of process on behalf of the represented party usually as required by statute c :  a person or organization that finds buyers or tenants for real estate owners usually for a commission d :  an independent sales or service representative of an insurance company — compare broker

  4. 4a :  a representative, emissary, or official of a government <a diplomatic agent> b :  an employee of a government agency usually that is involved in law enforcement

Seen and Heard

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a timid, meek, or unassertive person

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