quaking grass

WordReference Random House Unabridged Dictionary of American English © 2025

quak′ing grass′, 

1. Plant Biology any of several grasses of the genus Briza, having spikelets with slender, drooping stalks.

• 1590–1600

Collins Concise English Dictionary © HarperCollins Publishers::

quaking grass noun

1. any grass of the genus Briza, of N temperate regions and South America, having delicate flower branches that shake in the wind