Английский Этимологический словарь - green

- O.E. grene, earlier groeni, related to O.E. growan "to grow," from W.Gmc. *gronja-, from P.Gmc. base *gro- "grow," through sense of "color of living plants." Meaning of "a field, grassy place" was in O.E. The meaning "environmental" is attested from 1972; Greens "ecology political party," first recorded 1978, from Ger. die Grьnen (West Germany). Greenhorn was first "young horned animal" (1455), then "recently enlisted soldier" (1650), then "any inexperienced person" (1682). It contains the sense of green as "new, fresh, recent." Dollar bills have been greenbacks since 1870; but earlier bank paper money was called this since 1778. Greenland is O.N. Groenland, so named to induce settlers to go there. Green light in figurative sense of "permission" is from 1937.