From Longman Dictionary of Contemporary Englishthirtysomethingthir‧ty‧some‧thing /ˈθɜːtiˌsʌmθɪŋ $ ˈθɜːr-/ noun [countable] informalCLASS IN SOCIETY someone between the age of 30 and 39 a new magazine aimed at thirtysomethings —thirtysomething adjective
Examples from the Corpus
thirtysomething• As a twentysomething, I could see these thirtysomethings thought they had problems. 