: a hardy annual grass (Secale cereale) that is widely grown for grain and as a cover crop
: the seeds of rye used for bread flour, whiskey manufacture, feed for farm animals (as poultry), and especially formerly in the roasted state as a coffee substitute
Cerealgrass (Secale cereale) and its edible grain, used to make rye bread and rye whiskey, as livestock feed, and as a pasture plant. Native to South Asia, today it is grown extensively in Europe, Asia, and North America. It is planted mainly where climate and soil are relatively unfavourable for other cereals and as a winter crop where temperatures are too cold for winter wheat. Rye thrives at high altitudes and is the most winter-hardy of all small grains. It is high in carbohydrates and provides small quantities of protein, potassium, and B vitamins. Only rye and wheat have the necessary qualities to make a loaf of bread, but rye lacks the elasticity of wheat and thus is frequently blended with wheat flour. The tough fibrous straw of rye is used for animal bedding, thatching, mattresses, hats, and paper. Rye may be grown as a green manure crop.