Finding something humourous within something that is inherently tragic, disturbing, and/or absurd.
This word came to be when a group of friends were hanging out at a bar and one of them mentioned that they'd recently read a statistic that reported how every time the Special Olympics are held, someone dies because they push themselves too hard. People immediately began to laugh at this but also questioned themselves for doing so because it's clearly a tragic thing. Yet it seemed funny somehow. Sadlarious.