Top Definition
A event during sexual intercourse that a man ejaculates after only one pelvic thrust

hence the name

mono: one
stain: ejaculation
dude: was I any good
duedet: no, that was a complete monostain
by oliver (stoner 2277) February 07, 2009
Free Daily Email

Type your email address below to get our free Urban Word of the Day every morning!

Emails are sent from We'll never spam you.