A fanatic is someone who is extremely devoted to a cause or belief, often to the point of obsession. A BELIEVER is someone who has faith in a particular idea or concept, while a ZEALOT is someone who is passionate and enthusiastic about something. An ADDICT is someone who is addicted to something, while a DOGMATIST is someone who is rigidly devoted to a set of beliefs. A REVOLUTIONARY is someone who advocates for or participates in drastic change, while a CRANK is someone who holds EXTREME views on a subject. A MONOMANIAC is someone who is obsessed with one idea or subject, while an ACTIVIST is someone who actively works to bring about social or political change. EXTREME is an adjective used to describe someone who is very intense or passionate about something, while a BUG is a slang term for someone who is obsessed with something. A REBEL is someone who resists authority or convention, while a FREAK is someone who is considered strange or unusual. A NONCONFORMIST is someone who does not conform to the norms of society, while a BIGOT is someone who is intolerant of those who are different from them. A DEVOTEE is someone who is devoted to a particular cause or person, while ULTRA is an adjective used to describe someone who is extremely devoted to something. A NUT is a slang term for someone who is eccentric or obsessed with something, while a FIEND is someone who is intensely devoted to something. RABID is an adjective used to describe someone who is fanatical or EXTREME in their beliefs, while a MANIAC is someone who is driven by an obsession. A ZEALOT is someone who is fanatically devoted to a cause, while an obsessor is someone who is preoccupied with a particular idea or subject.