The term deja vu means already seen and it's the feeling that something has happened before. This is a familiar term and feeling. But there's another related term deja reve that means already dreamed. And it's the feeling that you previously dreamed what you are experiencing. There is some more nuance than that, but it's hard to clarify the random sources on the internet. I experience this one with some regularity.
I'm in a situation and I'll look in a certain direction or heard a specific sound and it will trigger the memory of the dream I know I had.
Again, the science behind this as explained by bloggers is not clear, so I will not try to summarize the summary. I'll leave it as it feels real, but it may not be.