WordWeb Online

1. Someone who is physiologically dependent on a substance or activity
    
2. Someone who is so ardently devoted to something that it resembles an addiction
   "a golf addict";
   - nut [informal], freak, junkie [informal], junky [informal]

1. To cause (someone or oneself) to become dependent (on something, especially a narcotic drug)
   - hook

Derived forms: addicts, addicted, addicting

Type of: accustom, drug user, enthusiast, habituate, partisan, partizan, substance abuser, user

Encyclopedia: Addict