Hey Dave -- what kind of harrow are you referring to?
I guess this is kind of like the difference between a pond and a tank -- it depends on where you live.
To me, a harrow is a row-crop tractor cultivator with spring teeth to control weeds in strawberry fields, potato patches, etc.
But, in my days of coaching youth sports, it was also a piece of chain link fence, with hooks and a cable that was dragged behind a lawn tractor to smooth the baselines of baseball fields.
Regards,
Ken