The Collaborative International Dictionary of English v.0.48:

Sturdy \Stur"dy\, a. [Compar. Sturdier; superl. Sturdiest.]
   [OE. sturdi inconsiderable, OF. estourdi stunned, giddy,
   thoughtless, rash, F. ['e]tourdi, p. p. of OF. estourdir to
   stun, to render giddy, to amaze, F. ['e]tourdir; of uncertain
   origin. The sense has probably been influenced by E. stout.]
   1. Foolishly obstinate or resolute; stubborn; unrelenting;
      unfeeling; stern.
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            This sturdy marquis gan his hearte dress
            To rue upon her wifely steadfastness. --Chaucer.
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            This must be done, and I would fain see
            Mortal so sturdy as to gainsay.       --Hudibras.
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            A sturdy, hardened sinner shall advance to the
            utmost pitch of impiety with less reluctance than he
            took the first steps.                 --Atterbury.
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   2. Resolute, in a good sense; or firm, unyielding quality;
      as, a man of sturdy piety or patriotism.
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   3. Characterized by physical strength or force; strong;
      lusty; violent; as, a sturdy lout.
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            How bowed the woods beneath their sturdy stroke!
                                                  --Gray.
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   4. Stiff; stout; strong; as, a sturdy oak. --Milton.
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            He was not of any delicate contexture; his limbs
            rather sturdy than dainty.            --Sir H.
                                                  Wotton.
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   Syn: Hardy; stout; strong; firm; robust; stiff.
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