noun \ˈā-jənt\

: 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

Full Definition of AGENT

:  one that acts or exerts power
a :  something that produces or is capable of producing an effect :  an active or efficient cause
b :  a chemically, physically, or biologically active principle
:  a means or instrument by which a guiding intelligence achieves a result
:  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>
:  a computer application designed to automate certain tasks (as gathering information online)

Examples of AGENT

  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 Kids

:  something that produces an effect <cleansing agents>
:  a person who acts or does business for another <a travel agent>
Medical Dictionary


noun \ˈā-jənt\

Medical Definition of AGENT

:  something that produces or is capable of producing an effect
:  a chemically, physically, or biologically active principle—see oxidizing agent, reducing agent
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