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English definition of “adult”

adult

noun [C] uk   /ˈæd.ʌlt/ /əˈdʌlt/ us  
A1 a person or animal that has grown to full size and strength: An adult under English law is someone over 18 years old. Adults pay an admission charge but children get in free.Kinds of menMen and womenKinds of womenMen and women

adult

adjective uk   /ˈæd.ʌlt/ /əˈdʌlt/ us  
A2 grown to full size and strength: an adult male/elephant She spent most of her adult life in prison.Physically and mentally mature and immature typical of or suitable for adults: Let's try to be adult about this.Physically and mentally mature and immature Adult films, magazines, and books show naked people and sexual acts and are not for children.Sexual devices and the sex industry
(Definition of adult from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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