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.
Defining 'Booster' in a General Sense. As far as college sports go, a booster is a very specific kind of athletics supporter, and NCAA has a lot of rules about what they can and cannot do (more on that later). At the same time, people use the term to describe all sorts of people who may not fit the NCAA's definition of a booster.