- grass roots (n.)
[grass roots 词源字典]
- 1650s, from grass + root (n.). The image of grass roots as the most fundamental level of anything is from 1901; U.S. political sense of "the rank and file of the electorate" (also grassroots) is attested from 1912; as an adjective by 1918.[grass roots etymology, grass roots origin, 英语词源]