grassyoudaoicibaDictYouDict[grass 词源字典]
grass: [OE] Reflecting its status as the commonest and most obvious of plants (and, for agricultural communities, the most important), grass etymologically simply means ‘that which grows’. It comes from *grō-, *gra-, the prehistoric Germanic base which also produced grow (and green). This gave the noun *grasam, from which German and Dutch get gras, Swedish gräs, and English grass.
=> graze, green, grow[grass etymology, grass origin, 英语词源]
grass (n.)youdaoicibaDictYouDict
Old English græs, gærs "herb, plant, grass," from Proto-Germanic grasan (cognates: Old Norse, Old Saxon, Dutch, Old High German, German, Gothic gras, Swedish gräs), from PIE *ghros- "young shoot, sprout," from root *ghre- "to grow, become green" (related to grow and green, but not to Latin gramen).

As a color name (especially grass-green, Old English græsgrene) by c. 1300. Sense of "marijuana" is recorded by 1932, American English. The grass skirt worn by people native to tropical regions is mentioned by 1874; the warning to keep off the grass by 1843 (in New York City's Central Park). Grass-fed of cattle, etc., (opposed to stall-fed) is from 1774.