Oat (noun)

1. A cereal plant that is the most important kind grown in cool climates, the grain of which is ground to make oatmeal.
2. The seed of this plant, used as animal feed and in baking and other foods.

Origin:

From old english word "æte" which means cereal plant.

Examples:

1. The farmer grew oats as a cash crop.
2. He had a bowl of oatmeal for breakfast.
3. The horse was fed oats twice a day.
4. Rolled oats are used to make oatmeal cookies.
5. Oat straw is used for animal bedding.