SOURCE OF THE OPA

OPA (ώπα) is a versatile Greek exclamation expressing enthusiasm, joy, surprise, or even a warning, similar to "Oops!" or "Hey!". It's widely used in celebrations, during dancing, and when something breaks or ... or is flambéed 🫵😲🔥

The exact meaning of "opa" depends heavily on context, evolving from ancient calls to "behold!" or "pay attention!" into a modern expression of cultural spirit, or "kefi".  

Synonyms for "opa" depend heavily on context and language; they can include grandfather (German/Dutch), granddad or grandpa (English informal), or an interjection meaning "oops," "watch out," "hey," or "come on" in Spanish, Greek, or Russian-influenced contexts. 

AND LAST BUT NOT LEAST: 

Take me to the Casino.