The small area of skin between the vagina or penis/ball sack and the anus that is particularly dirty and smelly because of a failed back to front wipe job. In other words, a taint with some shit on it.
Also known as taint, grundle or gooch.
I was railing my neighbor’s wife from behind when I began getting some wafts of dirty ass. I looked down to her Cincinnati bootstrap needed a bit of a wash.
I wiped my ass the wrong way cause I was in a hurry and gave myself a Cincinnati boot strap.
The homeless dude was washing his Cincinnati bootstrap in the Park fountain.