Definition of rattle grass in US English:

rattle grass

noun

  • 1Any of several kinds of rattle found as weeds in meadows and pastures, especially (more fully "red rattle grass") = "red rattle" (now rare).

  • 2Quaking grass, Briza media.

Origin

Late 16th century; earliest use found in Henry Lyte (1529–1607), botanist and antiquary.