A large amount of cum in a pile that has hardened over time.
I went over Matt's house yesterday and accidently stepped on his cum stone!
by Gavin Clarke May 21, 2007
A large mass of semen that has solidified in the testes due to extreme periods of time between ejaculations. A medical emergency, this occurrence causes immense pain upon expulsion from the glans. Not to be confused with "Cum Stone"
^^^SEE DEFINITION OF CUMSTONE^^^
by Dr. Mathulous September 07, 2011