Definition of rat's tail fescue in English:
rat's tail fescue
noun
An annual grass, Vulpia myuros, bearing long-awned spikelets in a long, narrow, one-sided panicle, occurring on walls and in other dry bare places in Eurasia and northern Africa.
Origin
Mid 19th century; earliest use found in George Bentham (1800–1884), botanist.
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