verb

• (transitive) To cause (someone or something) to have a light brown to brownish orange colour; to tan, to tawn.
  "So many friends, their friendſhips daily breake, / That fevve are faithfull, if that fevve be any: / The Sunne ſo ſoone, the painted face vvill tavvny."
• (intransitive) To become a light brown to brownish orange colour; to tan, to tawn.
  "The countenance alone bespoke the years and the cares of John M‘Whirter. The deep wrinkled brow—the cheek plaited, and tawnied in the sun and the frosts of the north— […]"

noun

• A light brown to brownish orange colour.
  "[T]he Herehaught [herald] muſt have a ſinguler reſpect to the face of him that ſhould haue the Armes, vvhere he ſhal vvel perceiue in vvhat ſeaſõ of the yere, his ovvn complexion vvill ſerue him to do beſt ſeruice in: […] If in Somer, either a Hound or Salamandra, or ſome part of them, of the colour Bruske, vvhich is betvveene Geules and tavvney."
• Something of a light brown or brownish orange colour (particularly if it has the word tawny in its name).
  "TAWNY. A bullfinch. Somerset."
• (alcoholic beverages) In full tawny port: a sweet, fortified port wine which is blended and matured in wooden casks.
  "Tawny is the most versatile Port style. The best tawnies are good-quality wines that have faded to a pale garnet or brownish red color during long wood aging. […] We consider 10- and 20-year-old tawnies the best buys; the older ones aren't always worth the extra bucks."
• (obsolete)
  "[N]o perſone, or perſones, occupiyng the ſeate of diẽg, ſhal die, or altre into colours, or cauſe to be died, or altred into colours, any wollen clothes, as broune blewes, pieukes, tawnies, or violettes, except the ſame wollẽ clothes be perfeictly boiled, greined or madered vpon the woade, & ſhot with good, and ſufficient corke, or orchal after a due, ſubſtancial, & ſufficient maner of workemanſhip, according to thauncient workmanſhip in time paſt vſed, vpõ peine for euery defalt to forfeite .xx. s̃."