what is woo
âWoo-wooâ is one of those terms that everyone kind of knows the definition of. âWoo-wooâ is one of those slang terms that everyone kind of knows the definition of, but here are a couple of official definitions (from the Internet, which is never wrong): Wiktionary.org says: âIt has been suggested that âwoo wooâ is intended to imitate the eerie background music of sci-fi/horror films and television shows, however the exact origin is uncertain.â