The Collaborative International Dictionary of English v.0.48:

Lusty \Lust"y\, a. [Compar. Lustier; superl. Lustiest.]
   [From Lust. See Lust, and cf. Luscious.]
   [1913 Webster]
   1. Exhibiting lust or vigor; stout; strong; vigorous; robust;
      healthful; able of body.
      [1913 Webster]

            Neither would their old men, so many as were yet
            vigorous and lusty, be left at home.  --Milton.
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   2. Beautiful; handsome; pleasant. [Obs.] --Spenser.
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   3. Of large size; big. [Obs.] "Three lusty vessels."
      --Evelyn. Hence, sometimes, pregnant. [Obs. or Prov.]
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   4. Lustful; lascivious. [Obs.] --Milton.
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WordNet (r) 3.0 (2006):

lusty
    adj 1: vigorously passionate [syn: lustful, lusty,
           concupiscent]
    2: endowed with or exhibiting great bodily or mental health; "a
       hearty glow of health" [syn: hearty, full-blooded,
       lusty, red-blooded]