type of plant, 1540s, from winter (n.) + green (n.). So called from keeping green through the winter.
Entries linking to wintergreen
winter n.
Old English winter (plural wintru), "the fourth and coldest season of the year, winter," from Proto-Germanic *wintruz "winter" (source also of Old Frisian, Dutch winter, Old Saxon, Old High German wintar, German winter, Danish and Swedish vinter, Gothic wintrus, Old Norse vetr "winter"), probably literally "the wet season," from PIE *wend-, nasalized form of root *wed- (1) "water; wet"). On another old guess, cognate with Gaulish vindo-, Old Irish find "white." The usual PIE word is *gheim-.
As an adjective in Old English. The Anglo-Saxons counted years in "winters," as in Old English ænetre "one-year-old;" and wintercearig, which might mean either "winter-sad" or "sad with years." Old Norse Vetrardag, first day of winter, was the Saturday that fell between Oct. 10 and 16.
green n.
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.