Hibachi chicken is chicken cooked on a charcoal powered grill, stove or hot plate. A hibachi is a type of cooking device, with a definition confined to a charcoal brazier covered by a grill in Japan, or with an expanded definition of any charcoal-powered stove or hot plate in North America.
Hibachi chicken is contingent on the method of cooking rather than the ingredients or flavor. In North America, the definition of the hibachi itself is different from Japan, so what constitutes hibachi chicken is different. In North America, the hibachi and teppanyaki cooking devices are often conflated. A teppanyaki is an iron grill with a flat surface powered by propane. A hibachi, historically, is different because it is powered by charcoal and has an open grate. However, because of the conflation in North America, chicken cooked on a teppanyaki could also be considered hibachi chicken.
Hibachi are generally portable, as opposed to the large non-portable teppanyaki. Traditional hibachi were heating devices and not used for cooking. In North America, the idea of hibachi or "hibachi-style" is linked to the use of teppanyaki to cook in front of a large party of guests. "Hibachi-style" cooking is characterized by the theatrical flare of the chefs who are able to toss ingredients, utensils, or create various effects with gas.