Deposting you semen in a girls belly button.

A very useful peice of scientific equipment but also an EPIC way to bamboozle friends and even enemys.
To call someone a petri dish is like calling sombody a douche bad or an idiot.

Someone who does not get penis

Chris Rigge petri dish

a person who is always sick and spreads their germs where ever they are.

Someone who has had sex with so many people that they are virtually guaranteed to have multiple STD's. Similar to a walking STD.

A game where doctors in a fertility clinic jack off into a petri dish with an egg in it. The last one to shoot their load has to say that they are the dad.