underage

 Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++un·der·age /ˌʌndərˈeɪdʒ◂/ adjective  PGCtoo young to legally buy alcohol, drive a car, vote etc 未成年的，未及法定年龄的 underage drinking 未成年饮酒

Examples from the Corpus

underage• They also express concern about the addiction and underage gambling they believe will be the inevitable partners of online gambling.• Tilden died broke, and shunned by many because of his conviction for homosexuality with underage partners.

un·der·age adjectiveChineseSyllable  

buy young a etc to legally alcohol, drive Corpus too car, vote

underage
un‧der‧age /ˌʌndərˈeɪdʒ◂/ adjective
too young to legally buy alcohol, drive a car, vote etc:
    underage drinking

under·ageBrE /ˈʌndəreɪdʒ/ 🔊NAmE /ˈʌndəreɪdʒ/ 🔊 adjective [only before noun] done by people who are too young by law 未达到法定年龄的人所做的；未成年人的◆underage drinking未成年饮酒  ➡  see also age noun