WordWeb Online

1. Changeable
   "freakish weather"
   - capricious
    
2. Characteristic of a freak
   "a freakish extra toe"
    
3. Conspicuously or grossly unconventional or unusual
   "a freakish combination of styles"
   - bizarre, eccentric, freaky, flaky, flakey, gonzo [N. Amer], off-the-wall, outlandish, outré

See also: abnormal, freakishly, freakishness, unconventional, unnatural, unpredictable

Encyclopedia: Freakish