An American woman living in Australia has revealed the very common Australian phrase that has left her feeling “gross”.

Australian water engineers put on an art exhibition with a difference on Wednesday, with an open-air display of decorated toilet bowls to raise awareness of the need to improve global sanitation.

An Australian passenger mistook the cockpit door for the toilet, triggering Friday's hijack scare on a Virgin Australia flight from Brisbane to the Indonesian holiday island of Bali, police said.