There is a micro-phenomenon of new wave, special snowflake directors that try to revolution the canons of classical opera. I saw Carmen being banged behind a burning car next to what looked like a flamenco-infused Thunderdome. That was in Paris opera, stronghold of modernist SJW nonsense.
Here, the expression is a shorter version of matriculation college. In a number of Canadian cities, many government-run secondary schools are called collegiates or collegiate institutes (C.I.), a complicated form of the word college which avoids the usual post-secondary connotation.
Try showing your friend my little Danish education word explanation: College = university. High school = gymnasium. HÃ¸jskole, although directly translated into high school it bears no resemblance to the American highschool, but is instead a place to go if you want to spend a year maybe focusing on art, exercise or music.