Betel nut is the nut that comes from a plant called Areca. It is sometimes used to make medicine. Betel nut is chewed alone or in the form of quids, a mixture of tobacco, powdered or sliced betel nut, and other ingredients. Betel nut is the nut that comes from a plant called Areca. It is sometimes used to make medicine. Betel nut is chewed alone or in the form of quids, a mixture of tobacco, powdered or sliced betel nut, and other ingredients.