Let's say an event organisation creates the concept of a new event where people gather to listen to music. It's going to be a recurring event taking place once every year. Whenever that event takes place, we call that 'an event'. Is there also a word for the concept/definition of the event? So not any of the instances of it, but rather the concept of it.
Update: It's not necessarily a musical event. It could be the concept of an outdoor activity. It could be the concept of prize winning pumpkins held annually. It could even be a recurring event where people are not gathering, but I can't think of an example yet.