Answer:
Deja vu is an IMPRESSION of having previously experienced something.
Explanation:
Example) While having a convo w/ someone, you may get the impression that the exact situation has played out before and that you have had this precise conversation w/ that individual.
Or while crossing a street (it could be something perfectly mundane)
It is not real, merely an impression. It is like recalling a memory that never happened. Generally w/in this life, not a past one.
