The missing middle refers to housing types that fall between single-family detached suburban homes and high-rise condos, such as duplexes, triplexes, fourplexes, and low-rise apartments.
As-of-right means that as long as you comply with municipal bylaws, there are no additional provisions required and you can go straight to a building permit without neighbor opposition.
A minor variance is an application used when you need to go outside current city bylaws, such as reducing parking requirements, and the case is heard before a committee of adjustments.