by Zoidberg101 March 2, 2011
The vagina. Described as such because of its likeness to a monster's mouth, but rotated counter-clockwise ninety degrees into a vertical position.
by Marimba Man July 4, 2009
When you take a shit and it ends up sideways in the toilet and it won't flush so you have to attack it with a toilet plunger
"The Sideways Monster has struck again"
by Sollarr January 30, 2018