成人の定義と意味 - メリアム・ウェブスター

ADULT Definition & Meaning - Merriam-Webster Est. 1828 Dictionary Definition adjective noun verb adjective 3 adjective noun verb 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 adult 1 of 3 adjective ə-ˈdəlt ˈa-ˌdəlt Synonyms of adult 1 : fully developed and mature : grown-up an adult lion 2 : of, relating to, intended for, or befitting adults an adult approach to a problem 3 : dealing in or with explicitly sexual material adult bookstores adult movies adulthood ə-ˈdəlt-ˌhu̇d noun adultly ə-ˈdəlt-lē ˈa-ˌdəlt- adverb adultness ə-ˈdəlt-nəs ˈa-ˌdəlt- noun adult 2 of 3 noun : one that is adult especially : a human being after an age (such as 21) specified by law adultlike ə-ˈdəlt-ˌlīk adjective adult 3 of 3 verb ə-ˈdəlt adulted ; adulting ; adults intransitive verb 1 informal : to behave like an adult : to attend to the ordinary tasks required of a responsible adult Do we really have to adult today? — Lauren Merola Stop complaining that you have to adult today. Being an adult is awesome. — Suzanne Lucas Learning how to " adult " is a necessity for these college freshmen in order to figure out new medication schedules and if their parents' insurance will cover impromptu ER visits. — Meredith Newman 2 informal : to become an adult It could be something small, like bailing on your friends at the last second. Or something bigger, like not showing up for work. Whatever the case may be, it's a sign you haven't fully " adulted " if you constantly slack off on your responsibilities. — Carolyn Steber But there is one real benefit to growing older and adulting : We essentially get to do whatever we want to do. — Sharon Pope Synonyms of adult Relevance Adjective mature Noun grown-up elder See All Synonyms & Antonyms in Thesaurus Examples of adult in a Sentence Adjective preparing children for adult life We need to approach this in an adult way. Noun Her books appeal both to children and to adults . Children must be accompanied by an adult in the museum. Only adults can purchase alcohol. This film is for adults only. Minors are not admitted. People who are close friends as children aren't always friends as adults . studying interactions between young birds and adults 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 . Adjective It is estimated that, based on measures of blood glucose, lipids, and other parameters, less than 12% of the adult American population can even be said to metabolically healthy. — Christopher Duggan, STAT , 27 Mar. 2026 For many readers and critics, the perception was that Mansfield was almost writing children’s fiction, since most of her stories are deceptively easy to read, although her themes are entirely adult in both form and content. — Literary Hub , 17 Dec. 2025 Noun But first, check if kids are welcome Resorts such as Anantara Veli Maldives Resort, Hurawalhi Island Resort, and Kudadoo Maldives are adults -only resorts. — Shradha Shahani, Condé Nast Traveler , 28 Apr. 2026 Another provision allows pharmacists to provide ivermectin, an anti-parasitic drug often prescribed for animals, over-the-counter for adults without a prescription. — Cbs Miami Team, CBS News , 28 Apr. 2026 Verb In January 2026, twin males were born to adult female Mafuko in the park’s Bageni family. — Ryan Brennan, Miami Herald , 8 Apr. 2026 At that hearing, Alex Adams, supervising deputy district attorney for the juvenile justice unit in the District Attorney’s Office, informed the judge of their motion to transfer the defendant to adult criminal court for prosecution. — Robert Salonga, Mercury News , 3 Apr. 2026 See All Example Sentences for adult Word History Etymology Adjective borrowed from French & Latin; French adulte, going back to Middle French, borrowed from Latin adultus, from past participle of adolēscere, adulēscere "to become mature, grow up," from ad- ad- + alēscere "to be nourished, grow up," probably inchoative derivative of *alēre "to grow," stative derivative of alere "to nurse, feed, nourish" — more at old entry 1 Noun derivative of adult entry 1 First Known Use Adjective 1531, in the meaning defined at sense 1 Noun 1655, in the meaning defined above Verb 1909, in the meaning defined at sense 2 Time Traveler The first known use of adult was in 1531 See more words from the same year Phrases Containing adult adult alternative adult education adult life adult - onset diabetes adult respiratory distress syndrome consenting adult pre - adult young adult Rhymes for adult consult exult insult iseult occult result catapult subadult cult See All Rhymes for adult Browse Nearby Words Adullamite adult adult alternative See all Nearby Words Articles Related to adult Adultism Prejudice or discrimination against young people as a group Adulting The verb 'adulting' is all grown up Cite this Entry Style MLA Chicago APA Merriam-Webster “Adult.” Merriam-Webster.com Dictionary , Merriam-Webster, https://www.merriam-webster.com/dictionary/adult. Accessed 6 May. 2026. Copy Citation Kids Definition adult 1 of 2 adjective ə-ˈdəlt ˈad-ˌəlt 1 : fully developed and mature 2 : of, relating to, or characteristic of adults adulthood ə-ˈdəlt-ˌhu̇d noun adultness ə-ˈdəlt-nəs ˈad-ˌəlt- noun adult 2 of 2 noun : a fully grown person, animal, or plant adultlike ə-ˈdəlt-ˌlīk adjective Etymology Adjective from Latin adultus "having grown up," from adolescere "to grow up" — related to adolescence Medical Definition adult 1 of 2 adjective ə-ˈdəlt ˈad-ˌəlt : fully developed and mature adult 2 of 2 noun 1 : one that has arrived at full development or maturity especially in size, strength, or intellectual capacity 2 : a human male or female after a specific age (as 18 or 21) Legal Definition adult noun : a person who has reached an age specified by law compare child , infant , minor More from Merriam-Webster on adult Nglish: Translation of adult for Spanish Speakers Last Updated: 29 Apr 2026 - Updated example sentences Love words? 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