addict, nut, freak, junkie, junky -- (someone who is so ardently devoted to something that it resembles an addiction; "a golf addict"; "a car nut"; "a bodybuilding freak"; "a news junkie")
Overview of verb freak
The verb freak has 1 sense
freak out, freak, gross out -- (lose one's nerve; "When he saw the accident, he freaked out")