A fork of Rural Dictionary
An unkempt female (or male!) nether region. When the pubic hairs are so long they get in the way of the urine stream and thus collect urine like a mop.
Now that she trimmed her piss-mop, Evilynne doesn't stain her britches.
A group act of defiance perpetrated by disgruntled employees, students or other activists that results in urine, rather than cleaning agent, to be unwittingly distributed on the floor of a relatively small, enclosed space; given sufficient time, the now ripened piss causes the air to become unbreathable, the facility itself rendered temporarily toxic.
We're all in this together; EVERYONE, even you ladies, gotta step-up and piss in the mop bucket! Now's our chance to get some payback!