Probably something along the lines of: Without accommodation, being able to learn, participate, and demonstrate competency in a series of courses which presume a student's mastery of information presented through secondary education.
Ok. If we take that definition, is there any reason a test shouldn't consider whether a student had a very good school and learned half of what they were given, or a very poor school and learned everything they were exposed to? (a contrived case, of course)