Oat (ōt), n.; pl.Oats (ōts). [OE. ote, ate, AS. āta, akin to Fries. oat. Of uncertain origin.] 1. (Bot.) A well-known cereal grass (Avena sativa), and its edible grain; — commonly used in the plural and in a collective sense.
2. A musical pipe made of oat straw. Milton.
Animated oatsorAnimal oats(Bot.), A grass (Avena sterilis) much like oats, but with a long spirally twisted awn which coils and uncoils with changes of moisture, and thus gives the grains an apparently automatic motion. — Oat fowl(Zoöl.), the snow bunting; — so called from its feeding on oats. — Oat grass(Bot.), the name of several grasses more or less resembling oats, as Danthonia spicata, D. sericea, and Arrhenatherum avenaceum, all common in parts of the United States. — To feel one's oats, to be conceited ro self-important. — To sow one's wild oats, to indulge in youthful dissipation. Thackeray. — Wild oats(Bot.), a grass (Avena fatua) much resembling oats, and by some persons supposed to be the original of cultivated oats.