Old English grene, Northumbrian groene "green, of the color of living plants," in reference to plants, "growing, living, vigorous," also figurative, of a plant, "freshly cut," of wood, "unseasoned" earlier groeni, from Proto-Germanic *grōni- (source also of Old Saxon grani, Old Frisian grene, Old Norse grænn, Danish grøn, Dutch groen, Old High German gruoni, German grün), from PIE root *ghre- "grow" (see grass), through sense of "color of growing plants."

From c. 1200 as "covered with grass or foliage." From early 14c. of fruit or vegetables, "unripe, immature;" and of persons, "of tender age, youthful, immature, inexperienced;" hence "gullible, immature with regard to judgment" (c. 1600). From mid-13c. in reference to the skin or complexion of one sick.

Green cheese originally was that which is new or fresh (late 14c.), later with reference to coloring; for the story told to children that the moon is made of it, see cheese (n.1). Green light in figurative sense of "permission" is from 1937 (green and red as signals on railways first attested 1883, as nighttime substitutes for semaphore flags). Green thumb for "natural for gardening" is by 1938. Green beret originally "British commando" is from 1949. Greenroom (also green room) "room for actors when not on stage" is from 1701; presumably a once-well-known one was painted green. The color of environmentalism since 1971.

Old English grenian "to become green, flourish" (see green (adj.)). Compare Dutch groenen, German grünen, Old Norse grona. Meaning "to make green" is 1560s. Related: Greened; greening.

late Old English, "green color or pigment, spectral color between blue and yellow;" also "a field, grassy place; green garments; green foliage," from green (adj.). Specific sense "piece of grassland in a village belonging to the community" is by late 15c. In golf, "the putting portion of the links" by 1849. Symbolic of inconstancy since late 14c., perhaps because in nature it changes or fades. Also symbolic of envy and jealousy since Middle English. Shakespeare's green-eyed monster of "Othello" sees all through eyes tinged with jealousy. "Greensleeves," ballad of an inconstant lady-love, is from 1570s. The color of the cloth in royal counting houses from late 14c., later the color of the cloth on gambling tables.

c. 1400, "vegetables;" 1690s, "freshly cut branches used for decoration," from green (n.). Meaning "ecology political party" first recorded 1978, from German die Grünen (West Germany), an outgrowth of Grüne Aktion Zukunft "Green Campaign for the Future," a mainly anti-nuclear power movement, and/or grüne Listen "green lists" (of environmental candidates). Green (adj.) in the sense of "environmental" is attested in English from 1971; Greenpeace, the international conservation and environmental protection group, is from 1971.

Old English grennes "green color; quality of being green," in plural, "green things, plants;" see green (adj.) + -ness. Meaning "immaturity" is from early 15c. Walpole coined greenth (1753) in the same sense.

as a color, a luminous, pale bluish-green, 1590s, from sea + green (adj.). As an adjective from c. 1600. Sea-green incorruptible was Carlyle's term for Robespierre.

town in Scotland just across the border, proverbial from late 18c. as the customery place for English couples to run off and be married without parental consent.

Old English græs, gærs "herb, plant, grass," from Proto-Germanic *grasan (source also of Old Frisian gers "grass, turf, kind of grass," Old Norse, Old Saxon, Dutch, Old High German, German, Gothic gras, Swedish gräs "grass"), which, according to Watkins, is from PIE *ghros- "young shoot, sprout," from root *ghre- "to grow, become green," thus related to grow and green, but not to Latin grāmen "grass, plant, herb." But Boutkan considers grāmen the only reliable cognate and proposes a substrate origin.

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.

1580s, "green in color; green with vegetation," from French virdeant "becoming green," present participle of Old French verdeiier "become green," from Vulgar Latin *viridiare "grow green, make green," from Latin viridis "green" (see verdure). Related: Verdantly; verdancy.

translating Old Norse Groenland, so named by its discoverer (986 C.E.) because "it would induce settlers to go there, if the land had a good name":

Hann gaf nafn landinu ok kallaði Groenland, ok kvað menn þat myndu fysa þangat farar, at landit ætti nafn gott. [ Islendingabok, 1122-1133]

See green (adj.) + land (n.). Related: Greenlander; Greenlandish.