look up any word, like cleveland steamer:
 
1.
The experience of feeling sure that one's hook up reminds them of a previous hook up.
Dude 1: "Damn I have this sinking feeling that I've motorboated those before"

Dude 2: "Sounds like Deja Boob to me."

Deja Vu
by D><K October 31, 2010
 
2.
When you could have sworn you've seen a pair of boobs before
oh, deja boobs!
by haydenjoey November 10, 2010
 
3.
the strange unsettling feeling that you have seen those breasts somewhere before.
when you're on the internet and you realize that the girl filling out that sweater is you're cousin, thats dejaboob.
by mr.nachos March 22, 2009
 
4.
Is the experience of feeling sure that one has already witnessed or experienced a current boob, even though the exact circumstances of the previous encounter are uncertain and were perhaps imagined
I had deja boob when molly took her shirt off
by Sil & Syd April 24, 2011