エージェントの定義と意味 - メリアム・ウェブスター

AGENT Definition & Meaning - Merriam-Webster Est. 1828 Dictionary Definition Definition Synonyms Example Sentences Word History Phrases Containing Rhymes Entries Near Related Articles Cite this Entry Citation Kids Definition Kids Medical Definition Medical Legal Definition Legal More from M-W Show more Show more Citation Kids Medical Legal More from M-W Save Word To save this word, you'll need to log in. Log In agent noun ˈā-jənt plural agents Synonyms of agent Simple Definition A Simple Definition is available from our Learner's Dictionary to help you understand the meaning faster. 1 : one that acts or exerts power 2 a : something that produces or is capable of producing an effect : an active or efficient cause Education proved to be an agent of change in the community. b : a chemically, physically, or biologically active principle an oxidizing agent 3 : a means or instrument by which a guiding intelligence achieves a result 4 : one who is authorized to act for or in the place of another: such as a : a representative, emissary, or official of a government crown agent federal agent b : one engaged in undercover activities (such as espionage) : spy a secret agent c : a business representative (as of an athlete or entertainer) a theatrical agent 5 : a computer application designed to automate certain tasks (such as gathering information online) agentive ˈā-jən-tiv adjective Synonyms of agent Relevance instrumentality means instrument vehicle agency mechanism factor organ See All Synonyms & Antonyms in Thesaurus Examples of agent in a Sentence They worked with a travel agent to plan their vacation. the whitening agent in the detergent is chlorine bleach Recent Examples on the Web Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback . Beyond the question of criminal referrals, the commission’s report urged DHS to restrict certain ICE and Customs and Border Protection practices, including the use of chemical agents , physical force and vehicle pursuits during civil immigration enforcement. — Olivia Olander, Chicago Tribune , 1 May 2026 At the time, Chesky revealed that Airbnb’s new AI customer service agent is built on 13 AI models, including one from Alibaba. — Emily Hallas, The Washington Examiner , 30 Apr. 2026 Beginning in the late 1970s, it was occupied by actor, puppeteer, and voice artist Chuck McCann and his wife, William Morris agent Betty Fanning, who lived there for 45 years until their deaths in 2018 and early 2026, respectively. — Wendy Bowman, Robb Report , 30 Apr. 2026 Over the past five weeks, Rubio, Sessions and influential GOP lobbyist Brian Ballard testified at the foreign- agent trial. — Miami Herald , 30 Apr. 2026 See All Example Sentences for agent Word History Etymology Middle English, "force capable of acting on matter," borrowed from Medieval Latin agent-, agens "something capable of producing an effect, person authorized to act for another," going back to Latin, present participle of agere "to drive (cattle), ride (a horse), be in motion, do, perform, transact," going back to Indo-European *h 2 eǵ- "drive," whence Sanskrit ajati "(s/he) drives," Greek ágein "to lead, carry off," Armenian acem "(I) lead," Old Irish ad- aig "drives, impels," Old Norse aka "to travel in a vehicle" First Known Use 15th century, in the meaning defined at sense 1 Time Traveler The first known use of agent was in the 15th century See more words from the same century Phrases Containing agent agent - general agent provocateur alkylating agent counter - agent county agent delta agent double agent estate agent extension agent free agent general agent Indian agent insurance agent literary agent nerve agent oxidizing agent press agent real estate agent reducing agent road agent secret agent special agent sub - agent ticket agent travel agent wetting agent See More Rhymes for agent newsagent reagent subagent See All Rhymes for agent Browse Nearby Words age norm agent agent cipher See all Nearby Words Articles Related to agent agentic Able to accomplish results with autonomy, used especially in reference to artificial intelligence Cite this Entry Style MLA Chicago APA Merriam-Webster “Agent.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/agent. Accessed 4 May. 2026. Copy Citation Kids Definition agent noun ˈā-jənt 1 a : something that produces an effect a cleansing agent b : a chemically, physically, or biologically active substance 2 : a person who acts or does business for another government agents a real estate agent Etymology Middle English agent "one that produces an effect," derived from Latin agere "to drive, act, do" — related to act , agile Medical Definition agent noun ˈā-jənt 1 : something that produces or is capable of producing an effect 2 : a chemically, physically, or biologically active principle see oxidizing agent , reducing agent Legal Definition agent noun 1 : someone or something that acts or exerts power : a moving force in achieving some result 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 a : 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 sense 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 perform — enrolled 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 a : 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 More from Merriam-Webster on agent Nglish: Translation of agent for Spanish Speakers Britannica.com: Encyclopedia article about agent Last Updated: 1 May 2026 - Updated example sentences Love words? 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