Lentil

a slight plant of the pea family. Lentil pods are short, broad, and very flat, containing two seeds. Lentils are a considerable article of food in the countries of the Mediterranean and the Orient. More people eat lentils than eat beans. Some are gray, others red. The mess of red pottage for which Esau sold Jacob his birthright is said to have been made of red lentils. The astronomer who ground a round piece of glass until it was thin at the edge and thick in the middle, like the familiar seeds that thickened his soup, called his new invention a lens or lentil.