The band's wild playing made the audience freak out.
The students freaked out when told that final exams were less than a week away.
It was such a close accident that it really freaked me out.
She freaked out and ended up in the psychiatric ward.
2. Experience or cause to experience hallucinations, paranoia, or other frightening feelings as a result of taking a mind-altering drug [Slang; mid-1960s]. For example:
They were freaking out on LSD or some other drug.
AVRIL LAVIGNE - FREAK OUT