When you and other people laugh non stop after smoking a good amount of weed (typically chronic). It can be triggered by something funny, something random, or something you wouldn't laugh at when sober. Length may vary depending on high but usually lasts a minute or two.
Dude: "Dude, what just happened?
Dude 2: "We just smoked a gram of Maui Wowie and had a 10 minute geek session when Chapelle came on."