"Opa" is a typical emotional term in the Mediterranean. In Greek culture, the term is frequently used in conjunction with plate smashing. It can also be used to convey excitement, astonishment or surprise, or simply after making a mistake. (source) In Italian culture, "Opa!" means good luck. Also an expression of admiration or respect. In Spanish culture, "Opa!" means good luck. In Turkish culture, "Opa!" means good luck.