It is more of a difference in British English, where a leash is used to control a large/dangerous animal, while a lead is used more cooperatively (like walking

It is more of a difference in British English, where a leash is used to control a large/dangerous animal, while a lead is used more cooperatively (like walking a dog). I heard lead quite a bit from trainers, and assume their choice in nomenclature is part of the general positive reinforcement nature of modern dog training.