'flip out' definitions:

Definition of 'flip out'

From: WordNet
verb
React in an excited, delighted, or surprised way; "he flipped when he heard that he was accepted into Princeton University" [syn: flip, flip out]
verb
Go mad, go crazy; "He flipped when he heard that he was being laid off" [syn: flip, flip out]

Synonyms of 'flip out'

From: Moby Thesaurus