Revelation, etymologically, means a ‘revealing’, and the word just means a revealing of knowledge.
Revelation occurs through things, the most obvious example being people who write things down.
How do they write things down? Well, they are inspired, which is a type of guidance.
In this sense, divine revelation occurs anytime someone is guided by God, whether that ends up in them writing something down or taking some other action.
According to Christianity, this isn’t some unique sort of event that occurred 2,000 years ago – people are constantly being guided by God, typically through the practice of discernment.
So, divine revelation is just guidance by God, whatever the action that follows from that is.