<p><strong>Noun</strong></p><ul><li>a cereal grass, <em>Avena sativa</em>, cultivated for its edible seed.</li><li>usually oats.</li><li>(used with a singular or plural verb) the seed of this plant, used as food for humans and animals.</li><li>any of several plants of the same genus, as the wild oat.</li><li>Archaic: a musical pipe made of an oat straw.</li></ul>