laughing fart 

A fart and a laugh together.

i.e. When someone cracks a joke in the company of distinguished guests and you let go a nice unmistakable fart during your laughter.

Prince Phillip: But Your Majesty there is no shame in a laughing fart! Here, let us all, ecstatically, fart in bonne homie!

laughing fart by NevermindWho April 13, 2006

The Laughing Farts 

When you have built up gas that you've been trying to hold in, and something makes you laugh. This results in a vicious cycle of losing control of your bowel and anal muscles and farting up a storm from the impact of the laughter, then laughing more at the farts, causing more farts, which causes more laughs, which causes more farts, and more laughs, and more farts until there is no gas left inside of you.

Farts usually expel in rhythmic timing according to the laughs. It's like unintentionally playing an instrument.

The Laughing Farts:
Yesterday at school I was holding in a fart, and my friend passed me a note that made me giggle, and I lost control for a second and blew a huge one. So then I started laughing even more and I farted even more and I had to run to the bathroom laughing and farting and the whole school was watching me. Traumatizing.

The Laughing Farts by Tatertawt24 August 21, 2012