species of hard wheat especially used in making macaroni, by 1904, from Latin durum, neuter of durus "hard," from PIE *dru-ro-, suffixed variant form of root *deru- "be firm, solid, steadfast." The seeds are tough. It was introduced in the U.S. by the Department of Agriculture in 1899 from Russia and 1900 from North Africa.
Previous to 1901 this wheat could not usually be sold at the elevators or mills at any price and was rarely grown—in small quantities only, for stock feed. Since its commercial value has been demonstrated the production has increased from 100,000 bushels, the largest estimate in 1901, to at least 6,000,000 bushels in 1903—an increase of sixtyfold in two years. [Flour Trade News, November 1904]