The Collaborative International Dictionary of English v.0.48:

Scarlet \Scar"let\, n. [OE. scarlat, scarlet, OF. escarlate, F.
   ['e]carlate (cf. Pr. escarlat, escarlata, Sp. & Pg.
   escarlata, It. scarlatto, LL. scarlatum), from Per.
   sakirl[=a]t.]
   A deep bright red tinged with orange or yellow, -- of many
   tints and shades; a vivid or bright red color.
   [1913 Webster]

   2. Cloth of a scarlet color.
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            All her household are clothed with scarlet. --Prov.
                                                  xxxi. 21.
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The Collaborative International Dictionary of English v.0.48:

Scarlet \Scar"let\, v. t.
   To dye or tinge with scarlet. [R.]
   [1913 Webster]

         The ashy paleness of my cheek
         Is scarleted in ruddy flakes of wrath.   --Ford.
   [1913 Webster] Scarmage

The Collaborative International Dictionary of English v.0.48:

Scarlet \Scar"let\, a.
   Of the color called scarlet; as, a scarlet cloth or thread.
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   Scarlet admiral (Zool.), the red admiral. See under Red.
      -- Scarlet bean (Bot.), a kind of bean (Phaseolus
      multiflorus) having scarlet flowers; scarlet runner.

   Scarlet fever (Med.), a contagious febrile disease
      characterized by inflammation of the fauces and a scarlet
      rash, appearing usually on the second day, and ending in
      desquamation about the sixth or seventh day.

   Scarlet fish (Zool.), the telescope fish; -- so called from
      its red color. See under Telescope.

   Scarlet ibis (Zool.) See under Ibis.

   Scarlet maple (Bot.), the red maple. See Maple.

   Scarlet mite (Zool.), any one of numerous species of bright
      red carnivorous mites found among grass and moss,
      especially Thombidium holosericeum and allied species.
      The young are parasitic upon spiders and insects.

   Scarlet oak (Bot.), a species of oak (Quercus coccinea)
      of the United States; -- so called from the scarlet color
      of its leaves in autumn.

   Scarlet runner (Bot.), the scarlet bean.

   Scarlet tanager. (Zool.) See under Tanager.
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WordNet (r) 3.0 (2006):

scarlet
    adj 1: of a color at the end of the color spectrum (next to
           orange); resembling the color of blood or cherries or
           tomatoes or rubies [syn: red, reddish, ruddy,
           blood-red, carmine, cerise, cherry, cherry-red,
           crimson, ruby, ruby-red, scarlet]
    n 1: a variable color that is vivid red but sometimes with an
         orange tinge [syn: scarlet, vermilion, orange red]