活動の定義と意味 - メリアム・ウェブスター

ACTIVITY Definition & Meaning - Merriam-Webster Est. 1828 Dictionary Definition Definition Synonyms Example Sentences Word History Phrases Containing Rhymes Entries Near 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 activity noun ac·​tiv·​i·​ty ak-ˈti-və-tē plural activities Synonyms of activity Take our 3 question quiz on activity 1 : the quality or state of being active : behavior or actions of a particular kind physical activity criminal activity economic activity Take our 3 question quiz on activity 2 : vigorous or energetic action : liveliness a scene of excitement and activity 3 : natural or normal function: such as a : a process (such as digestion) that an organism carries on or participates in by virtue of being alive b : a similar process actually or potentially involving mental function specifically : an educational procedure designed to stimulate learning by firsthand experience 4 : an active force 5 a : a pursuit in which a person is active business activities social activities b : a form of organized, supervised, often extracurricular recreation The camp offers hiking, swimming, and other activities . 6 : an organizational unit for performing a specific function also : its function or duties the restaurant inspection activity of the health department Synonyms of activity Relevance exertion conditioning exercise See All Synonyms & Antonyms in Thesaurus Examples of activity in a Sentence The holidays always set off a lot of activity in our home. the sexual activity of married couples The police are now monitoring criminal activity in the area. She gets at least 30 minutes of physical activity every day. The instruments are used to detect volcanic activity on the island. We planned an activity for the children. 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 . The planet no longer has active plate tectonics and only experienced more significant geological activity in its distant past. — Ryan Brennan, Miami Herald , 27 Apr. 2026 Gregory Bovino, the controversial head of aggressive enforcement activities in Chicago and Minneapolis, resigned from the agency. — Rick Pearson, Chicago Tribune , 27 Apr. 2026 Human oversight remains part of the workflow through integration with Robotic Security Operations Center, where remote analysts monitor activity , verify alerts, and direct responses when required, ensuring continuous supervision alongside autonomous functions, reports Electrek. — Jijo Malayil, Interesting Engineering , 27 Apr. 2026 The report actually describes something that sounds like Google’s Magic Cue, which relies on Gemini to offer suggestions based on your activity . — Robert Pearlman, ArsTechnica , 27 Apr. 2026 See All Example Sentences for activity Word History Etymology Middle English actyvete "active life," borrowed from Middle French & Medieval Latin; Middle French activité "power of acting, exercise of this power," borrowed from Medieval Latin āctīvitāt-, āctīvitās (Late Latin, "active form of a verb"), from Latin āctīvus active entry 1 + -itāt-, -itās -ity First Known Use 15th century, in the meaning defined at sense 1 Time Traveler The first known use of activity was in the 15th century See more words from the same century Phrases Containing activity bitten by the (activity) bug co - activity optical activity self - activity Rhymes for activity acclivity captivity declivity festivity nativity passivity proclivity absorptivity affectivity collectivity conductivity connectivity See All Rhymes for activity Browse Nearby Words activist activity activity cage See all Nearby Words Cite this Entry Style MLA Chicago APA Merriam-Webster “Activity.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/activity. Accessed 5 May. 2026. Copy Citation Kids Definition activity noun ac·​tiv·​i·​ty ak-ˈtiv-ət-ē plural activities 1 : the quality or state of being active 2 : forceful or energetic action 3 : a natural, normal, or assigned function: as a : a process that an organism carries on or participates in by virtue of being alive b : a similar process that involves or is capable of involving mental function 4 : an educational exercise designed to teach by firsthand experience 5 : an active force solar activity 6 a : something done especially for relaxation or fun b : a form of organized recreation Medical Definition activity noun ac·​tiv·​i·​ty ak-ˈtiv-ət-ē plural activities 1 : natural or normal function: as a : a process (as digestion) that an organism carries on or participates in by virtue of being alive b : a similar process actually or potentially involving mental function specifically : an educational procedure designed to stimulate learning by firsthand experience 2 : the characteristic of acting chemically or of promoting a chemical reaction the activity of a catalyst More from Merriam-Webster on activity Nglish: Translation of activity for Spanish Speakers Britannica.com: Encyclopedia article about activity Last Updated: 28 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! Merriam-Webster unabridged More from Merriam-Webster Word of the Day augur See Definitions and Examples » Get Word of the Day daily email! Popular in Grammar & Usage See More More Commonly Mispronounced Words 5 Verbal Slip Ups and Language Mistakes Is that lie 'bald-faced' or 'bold-faced'? The Difference Between 'i.e.' and 'e.g.' Why is '-ed' sometimes pronounced at the end of a word? See More Popular in Wordplay See More The Longest Long Words List 9 Other Words for Beautiful The Words of the Week - May 1 Why do we 'bury the lede?' 10 Words for Food with Unfortunate-Sounding Names See More Popular See More More Commonly Mispronounced Words The Longest Long Words List 9 Other Words for Beautiful See More Games & Quizzes See All Quordle Can you solve 4 words at once? Play Blossom Pick the best words! 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