Four leaf blover 

Oral sex (or a blow job) that was received on Saint Patrick' Day

Jeff: What are you doing on St. Patty's day?

Justin: I hope my girlfriend gives me some guinness and a four leaf blover.

Four leaf blover by CoWB07 March 28, 2009

Four Leaf Blowver 

On St. Patrick's Day four guys cover their erections in green frosting and place them on a fifth party's face, the "Four Leaf Blowver" is the process in which the fifth party member sucks the frosting off each erection. When all the frosting is sucked off of the erections the "Four Leaf Blowver" is complete.

Person A: Who do you think performed a better Four Leaf Blowver last St. Patrick's Day, Dave or Stephanie?

Person B: I hate to say it but I think it was Dave who performed the better Four Leaf Blowver!

This year's Four Leaf Blowver was amazing! Our cocks were green, our semen was white, and Carrie's hair was orange; her head looked like the Irish Flag.

Four Leaf Blowver by Dan Podgorni September 2, 2013