The Collaborative International Dictionary of English v.0.48:

Doughty \Dough"ty\ (dou"t[y^]), a. [Compar. Doughtier
   (dou"t[i^]*[~e]r); superl. Doughtiest.] [OE. duhti, dohti,
   douhti, brave, valiant, fit, useful, AS. dyhtig; akin to G.
   t["u]chtig, Dan. dygtig, Sw. dygdig virtuous, and fr. AS.
   dugan to avail, be of use, be strong, akin to D. deugen, OHG.
   tugan, G. taugen, Icel. & Sw. duga, Dan. due, Goth. dugan,
   but of uncertain origin; cf. Skr. duh to milk, give milk,
   draw out, or Gr. ty`chh fortune. [root]68.]
   Able; strong; valiant; redoubtable; as, a doughty hero.
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         Sir Thopas wex [grew] a doughty swain.   --Chaucer.
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         Doughty families, hugging old musty quarrels to their
         hearts, buffet each other from generation to
         generation.                              --Motley.
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   Note: Now seldom used, except in irony or burlesque.
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