Deja vu is defined as the sometimes creepy feeling that you have been somewhere before or had a specific experience before, even if you really haven't.(noun)
An example of deja vu is when you walk into a house and are sure you have already seen it because it is so familiar when in reality you haven't.
See déjà vu in American Heritage Dictionary 4
Origin: : déjà, already
Origin: + vu, seen.
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