An ink fluid mark of a teardrop located under the eye, usually used to signify a commited murder. The teardrop is also used to display endless sorrow, such as the loss of a close friend, or life sentence in prison.
A memory that one has that one can never forget and every so often it comes around and you have to deal with it.
Man1:I saw my grandmas pie and I can't get it out of my mind it's tattooed on my brain.
Man2: It's your memory so don't give it to me.
Man1:I wish the brain had an erase botton.