A term used to describe the act of inhaling something (such as: weed, something containing nicotine, or maybe even ethyl-chloride (wouldn't recommend at all it's very dangerous) ) and then passing the joint/cigarette/vape to a friend whilst holding your breath until they pass it back to you then you exhale, take some more and then pass it back to your friend. You continue this cycle until you become extremely high (or if you're doing it with cigs or a vape it just gives you a massive headspin to the point where you feel yourself sinking into the floor).
Sofia: Yo me and Brent did a suicide high yesterday.
Daniel: Wow you two are really fucking dumb.
Another name for Kitscoty high school that started in the 90s for obvious reasons