Okay
Let me tell you. This is untainted. And it isn't anywhere on the web.
Deja vu is French.
Deja - Already
Vu - Seen (from verb voir - to see)

So, roughly, deja vu translates to already seen
But, in English, it means a feeling of something you have already experienced. Only a person who has experienced deja vu can accurately understand it.

One more thing: you don't create deja vu.

it simply means that describes the experience of feeling that one has witnessed or experienced a new situation previously or An impression of having seen or experienced something before