lentil

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A leguminous plant (Lens culinaris) native to southwest Asia, having flat pods containing lens-shaped, edible seeds.
• noun The round, flattened seed of this plant.

from The Century Dictionary.

• noun A body or mass having the general form of a double-convex lens; a lenticular body or mass; a lenticle.
• noun The annual leguminous plant Lens esculenta, or its seeds.
• noun plural Freckles; lentigo.
• noun In apparatus for rectifying alcohol, one of the lentil-shaped bulbs (of which there are generally two, but may be more) placed in the condenser between the coil and the pipe leading from the column of the still. See still and rectification.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Bot.) A leguminous plant of the genus Ervum (Ervum Lens), of small size, common in the fields in Europe. Also, its seed, which is used for food on the continent.
• noun (Zoöl.) a small bivalve shell of the genus Ervillia, family Tellinidæ.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Any of several plants of the genus Lens, especially Lens culinaris, from southwest Asia, that have edible, lens-shaped seeds within flattened pods.
• noun The seed of these plants, used as food.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun widely cultivated Eurasian annual herb grown for its edible flattened seeds that are cooked like peas and also ground into meal and for its leafy stalks that are used as fodder
• noun the fruit or seed of a lentil plant
• noun round flat seed of the lentil plant used for food