ruefully

from WordNet (r) 3.0 (2006)

ruefully
    adv 1: in a rueful manner; "`I made a big mistake,' he said
           ruefully" [syn: {ruefully}, {contritely}, {remorsefully}]

from The Collaborative International Dictionary of English v.0.48

Rueful \Rue"ful\ (r[udd]"f[.u]l), a.
   1. Causing one to rue or lament; woeful; mournful; sorrowful.
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   2. Expressing sorrow. "Rueful faces." --Dryden.
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            Two rueful figures, with long black cloaks. --Sir W.
                                                  Scott.
      [1913 Webster] -- {Rue"ful*ly}, adv. -- {Rue"ful*ness}, n.
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