So this is what I get from dictionary.com:
- a number of persons or things regarded as forming a group by reason of common attributes, characteristics, qualities, or traits; kind; sort: a class of objects used in daily living.
- any collection or assemblage of persons or things; cluster; aggregation: a group of protesters; a remarkable group of paintings.
- a number of persons or things ranged or considered together as being related in some way.
The other dictionaries don't seem to be much different. But I always thought that "class" was one of the set of properties of which objects could be differentiated, while "group" is a set of objects having such properties. Classes would be expected to overlap, groups would more likely be distinct. Given a population of objects, the union of all groups within any single class would combine to be the entire population.
I.e. gender is the class, while male or female are groups defined by that class. Age would be a class, while minors and adults would be groups in that class.
That's what I thought was meant, but I can't tease that out of these definitions, so I guess I have for decades a misconception of meaning.
Is that right? Had I had this wrong for all these years? Or am I just not reading these definitions correctly? They seem to be defining "class" and "group" virtually synonymously.