I'm Jacknifing – I'm Laughing Really Hard

Dec 2009 – original post

To Jacknife – when you burst out laughing, so hard and so suddenly, you involuntarily fold in half at the waist.
Usually accompanied by a large exhale of breath.

Got it into UrbanDictionary.com

(here’s the original post and video)

The origins of the word go back to the ’09 post, and further #BenefitOfBlogging

Another time I visualized my laugh, click here to see.

(I’d forgotten about this video until last night, went and watched it, which is why this post)