addict
/əˈdɪkt/noun
1- a person who is addicted to a particular substance, typically an illegal drug（尤指毒品）上瘾者。
1.1
- with modifier informal an enthusiastic devotee of a specified thing or activity〈非正式〉入迷的人：
a self-confessed chocolate addict.
自认不讳的巧克力瘾君子。
词源
early 20th cent.: from the obsolete verb addict, which was a back-formation from ADDICTED.