The Collaborative International Dictionary of English v.0.48:

Winsome \Win"some\, a. [Compar. Winsomer; superl.
   Winsomest.] [AS. wynsum, fr. wynn joy; akin to OS. wunnia,
   OHG. wunna, wunni, G. wonne, Goth. wunan to rejoice (in
   unwunands sad), AS. wunian to dwell. ????. See Win, v. t.,
   Wont, a.]
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   1. Cheerful; merry; gay; light-hearted.
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            Misled by ill example, and a winsome nature.
                                                  --Jeffrey.
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   2. Causing joy or pleasure; gladsome; pleasant.
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            Still plotting how their hungry ear
            That winsome voice again might hear.  --Emerson.
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