/ˈʌndərˌeɪdʒ/ – adjective
Definition: dưới tuổi vị thành niên
A more thorough explanation: 1. (of a person) under the legal age limit for a particular activity such as drinking alcohol or having sex
2. (of an activity) done by people who are younger than the legal age limit
Example: 1. He was convicted of paying for sex with an underage prostitute.
2. The new law will also create new offences aimed at tackling underage drinking.