chuckle without the chunks 

To issue an unintentional fart (or series thereof) when laughing uncontrollably at an unexpected funny moment. Importantly, this is not followed by "following through", which would spoil the moment, hence "no chunks". Often associated with ejecting beer, etc from the nose at funny moments.

HaHaHa..Frrt,frrt,frrt....I just wasn't expecting that punchline! Damn, I chuckled without the chunks

chuckle without the chunks by Mister Gruntfuttock August 24, 2005