vacation brain 

the 1-2 days before vacation when you can't get much work done because your brain is already on vacation

I haven't been able to get shit done at work today. I have vacation brain.

vacation brain by juswannabangonmedrumallday November 24, 2009

vacation brain 

When you feel like you're on vacation and you actually aren't.

Dude: Brooo forget the meeting, let's go to the beach!
Colleague: You've got a serious case of vacation brain. I have to get back to work.

vacation brain by chacarron March 6, 2012