1. Psychology. The illusion of having already experienced something actually being experienced for the first time.
2. 1. An impression of having seen or experienced something before: Old-timers watched the stock-market crash with a distinct sense of déjà vu.
   2. Dull familiarity; monotony: the déjà vu of the tabloid headlines.

[French : déjà, already + vu, seen.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.