Soap used for cleansing the brain of a disturbing image or words that just wont leave.
Can also be spelled without a space, as Brainsoap
"I think i need some serious brain soap after seeing that"
p1-"That image is now forever burned into my retinas... "
p2-"Not with brain soap!" *hands brain soap*
p1-"ahh brain soap"
p2-"so what was that image?"