farthingale n.

late 14c., "fresh green color," from Old French verdure "greenness, greenery, green fields, herbs," from verd, variant of vert "green" (12c.), from Latin viridis (source of Spanish, Italian verde), related to virere "be green," of unknown origin. Perhaps ultimately from a root meaning "growing plant" and cognate with Lithuanian veisti "propagate," Old Norse visir "bud, sprout," Old English wise "sprout, stalk, etc." But de Vaan writes that "None of the adduced set of cognates (Lat. 'green', Baltic 'multiply, fruit', Gm. 'sprout, meadow') undoubtedly belong together." Meaning "green plants, vegetation" is attested from c. 1400.

1580s, "strap passing between the forelegs of a horse as part of the harness," from French martingale (16c.), of uncertain origin, perhaps from Old Provençal martegalo, fem. of martegal "inhabitant of Martigue," a commune northwest of Marseilles, making the etymological sense "worn in the manner of the people of Martigue;" or perhaps it is from Spanish almartaga, a word for a sort of halter or rein, from Arabic almartak, in which case it might have been influenced in form by the Provençal word. The nautical sense of  "short, perpendicular spar under the bowsprit-end" is by 1794.