this is the white residue left on your clothes (usually inside your jeans) from 1-3 day old jackoff semen that you forgot to clean and now has become a chalk-like powder that kinda flakes off when you scratch it with your nail, wondering what it is...
Ernie, this cock chalk all over your clothes is out of control!!!! Please son, stop jacking off so much.
by 777geez October 4, 2015
What you call it when you write on something with your cock after you bone some chick on her period.
by Chuck Bucket February 18, 2005
by lakeguy March 20, 2009