The feeling of not belonging to any place, time, or reality. Or perhaps the time/place/reality doesn't belong to you - as if something is deeply wrong with the way the entire world around you is, but you can't quite remember or perceive why.
"You seem out of it."
"I guess I am. I just woke up this morning feeling so yearless - even the sound of your voice sounds like it came from a dream."
"Oh. That's not good."