1. To be day dreaming and unaware of the things around you. You usually appear to be staring at something, when in fact you are just looking in one place and you are deep in thought, or your mind is blank and you are trying to find yourself. Often people will wave their hand in front of your face and make a huge deal out of getting you to 'come back to earth'
2.A lot of times people that self-harm will "zone out" before they do it. This simply means that they seem to block out everything around them and can no longer reconize where they are, nor can they feel pain.
1. Becca was so bored in history class that she zoned out, so Tyler started to wave his hands in front of her to make her snap out of it.