行動の定義と意味 - メリアム・ウェブスター

BEHAVIOR 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 More from M-W Show more Show more Citation Kids Medical More from M-W Save Word To save this word, you'll need to log in. Log In behavior noun be·​hav·​ior bi-ˈhā-vyər bē- Synonyms of behavior Take our 3 question quiz on behavior 1 : the way in which someone conducts oneself or behaves (see behave sense 1 ) We were grateful for the gracious behavior of our hostess. The children were rewarded for good behavior . Be on your best behavior . also : an instance of such behavior unacceptable social behaviors Take our 3 question quiz on behavior 2 a : the manner of conducting (see conduct entry 1 sense 2 ) oneself criminal behavior normal adolescent behavior b : anything that an organism does involving action and response to stimulation c : the response of an individual, group, or species to its environment They are studying the behavior of elephants in the wild. 3 : the way in which something functions or operates They tested the behavior of various metals under heat and pressure. Synonyms of behavior Relevance actions demeanor attitude See All Synonyms & Antonyms in Thesaurus Examples of behavior in a Sentence I'm surprised by her bad behavior toward her friends. Students will be rewarded for good behavior . scientists studying the behavior of elephants An acceptable social behavior in one country may be unacceptable in another country. Doctors are trying to educate people about behaviors that can put them at increased risk for skin cancer. The experiment tested the behavior of various metals under heat and pressure. See More 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 . Johnston pointed to Dukes’ criminal behavior and history. — Tess Kenny, Chicago Tribune , 29 Apr. 2026 The strategy was discovered by accident in 2022, when researchers were studying the movement and behavior of small mammals along Florida’s southern coast. — Hanna Wickes, Kansas City Star , 28 Apr. 2026 The same appears to be true of douchey athlete Hutch (Lakota Johnson), whose aggressive behavior with Lilly (Zhao Simei) pisses off Sam (Li Wenhan), captain of the Esports team returning from a video gamer tournament. — David Rooney, HollywoodReporter , 28 Apr. 2026 Doe claims school officials knew or should have known about O’Brien’s behavior , including prior reports of abuse involving other students, but failed to take action. — Lexi Nicklaus, Baltimore Sun , 28 Apr. 2026 See All Example Sentences for behavior Word History Etymology alteration of Middle English behavour , from behaven "to behave " + -our -or entry 2 First Known Use 15th century, in the meaning defined at sense 1 Time Traveler The first known use of behavior was in the 15th century See more words from the same century Phrases Containing behavior behavior modification behavior therapy cognitive behavior therapy for good behavior on one's best behavior on their best behavior Rhymes for behavior behaviour havior savior saviour misbehavior misbehaviour See All Rhymes for behavior Browse Nearby Words behave behavior behavioral See all Nearby Words Articles Related to behavior Odd Habits and Quirks Are you the kind of person who tends to cavil? Cite this Entry Style MLA Chicago APA Merriam-Webster “Behavior.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/behavior. Accessed 4 May. 2026. Copy Citation Kids Definition behavior noun be·​hav·​ior bi-ˈhā-vyər 1 : the way in which one conducts oneself 2 : the way in which something (as a machine) behaves 3 : anything that a living being does that involves action and response to stimulation behavioral -vyə-rəl adjective Medical Definition behavior noun be·​hav·​ior variants or chiefly British behaviour bi-ˈhā-vyər 1 : the manner of conducting oneself 2 a : anything that an organism does involving action and response to stimulation b : the response of an individual, group, or species to its environment behavioral adjective or chiefly British behavioural -vyə-rəl behaviorally adverb or chiefly British behaviourally -rə-lē More from Merriam-Webster on behavior Nglish: Translation of behavior for Spanish Speakers Last Updated: 29 Apr 2026 - Updated example sentences Love words? Need even more definitions? Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free! 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