"Freak" refers (be it a person, a thing or occurrence ) to something that is noticeably unusual, irregular or strange due to its unusual appearance or behavior. An abnormally formed organism for example ,whether a person or an animal will be regarded with curiosity and named 'freak'. A person acting weird and unusual could be also called ' a freak'. Another meaning of 'freak' is a sudden, impulsive or unpredictable turn of mind. "The freaks of the psyche are hardly explained." As a slang word it could refer to a drug user or addict, an eccentric or nonconformist person or an enthusiast ,showing extreme interest and dedication to something such as a rock music freak , a computer freak etc... That was about 'freak' the noun, as for the verb 'to freak' it means experiencing ( or causing to experience) frightening hallucinations ,especially as a result of taking a drug. It is usually used with ' out' ( to freak out). It also means to behave irrationally and uncontrollably under certain circumstances causing one to be upset and greatly excited.

Adjective: unusual; odd; irregular: a freak epidemic. Verb (used without object), verb (used with object) - to become or make frightened, nervous, or wildly excited: The loud noise caused the horse to freak. Verb phrase . freak out, ...Slang . a. to enter into or cause a period of irrational behavior or emotional instability, as under the influence of a drug: to be freaked out on LSD. b. to lose or cause to lose emotional control from extreme excitement, shock, fear, joy, despair, etc.: Seeing the dead body freaked him out. http://dictionary.reference.com/browse/freak

freak = extremely unusual thing or person Can be good or bad.

eliot is a freak

so it really depends on the context :)