any grass of the genera Aira, Deschampsia, etc, having very narrow stems and leaves
hair grass in American English
noun
any of various grasses having slender stems and leaves, esp. one of the genus Deschampsia, as D. flexuosa or D. caespitosa
Word origin
[1750–60]This word is first recorded in the period 1750–60. Other words that entered Englishat around the same time include: Yankee, bunker, permeability, summation, swish