Midi bus with rear-mounted engine. Photo: Temsa.
The term midi bus is sometimes used to indicate a mid-sized bus. But the opinions on what is mid-sized vary wildly. So we do not use the term.
If a bus loads up to 25-30 passengers without luggage, or up to 15-20 with luggage, and has the engine in the front, we call it a minibus.
We define all other buses by the type of service they are designed for.