1. noun /friːk/
a) A sudden causeless change or turn of the mind; a whim of fancy; a capricious prank; a vagary or caprice.
Bobs a real video-game freak. He owns every games console of the last ten years.
b) A nonconformist, especially in appearance, social behavior, sexual orientation, gender identity, and/or business practices; an oddball, especially in physiology (i.e., "circus freak"); unique, sometimes in a displeasing way.
2. verb /friːk/
a) To make greatly distressed and/or a discomposed appearance
But after one night turned into five days, I was freaking out. I missed him.
"[...] Harvard have compiled a list of LSDs contributions—largely missing before then—to our popular language: turned on, straight, freak, freaked out, stoned, [...]"
3. adjective /friːk/
Wikipedia foundation.