Laughed Until Snot Came Out
...from your nose.
This word is used when one laughs at a joke or an act so hard that it has gone way beyond 'lol-ing' and 'lmao-ing'.
The level of hilarity has reached a point where the vocal expulsion of air from the lungs have not only resulted into an audible, vocal sound, but has also pushed the remaining 'snot' from the nasal cavity. Thus excreting snot out of the nose while laughing.
Holy shit! Did you see that donkey on a skateboard?? I just fucking lusco'd man.