Lewis & Short

hordĕum (also ordeum, and arch. fordeum acc. to Quint. 1, 4, 14), i. n. [Sanscr. root ghars-, to rub, grind; O. H. Germ. Gers-ta], barley, Plin. 18, 7, 10, § 58; Cato, R. R. 35, 2; Varr. R. R. 2, 4, 6; Col. 2, 9, 3 sq.; Liv. 27, 13, 9; Suet. Aug. 24: frugibus legatis hordeum continetur, Paul. Sent. 3, 6, 78.
In plur., Verg. E. 5, 36; id. G. 1, 317; on account of this plur. he was abused by the poet Bavius; v. Bavius; cf. also: hordea et mulsa non alio vitiosa sunt, quam quod singularia pluraliter efferuntur. Quint. 1, 5, 16; plur. also Plin. 18, 7, 10, § 56.