Verb. To undo the act of seeing something; to erase the memory of having seen something, or otherwise reverse the effect of having seen something.

Adj. Used to describe an object so horrific that it becomes seared into your retinas such that it can never be forgotten.

See also: goatse, tubgirl, What the fuck, goggles

When you see someone you may know and the two of you look at each other for a few seconds and ask each other to unsee each other.Baisically seeing a freind of yours in public and you both act like you did not just see each other .