it's defined by the main level being raised above the entry level, whether thats entry through the basement level, or entry in-between the basement & main level
https://www.ehow.com/info_8469574_raised-ranch-house.html
"A traditional ranch style home translates to mean a single level of living space. A raised ranch is one type of bi-level home design. The living area is actually raised off the ground even though the entryway is at ground level. The true test of a raised ranch style house is entering the front door and then having to climb a set of stairs to access the living area of the house."