The Collaborative International Dictionary of English v.0.48:

Damsel \Dam"sel\ (d[a^]m"z[e^]l), n. [OE. damosel, damesel,
   damisel, damsel, fr. OF. damoisele, damisele, gentlewoman, F.
   demoiselle young lady; cf. OF. damoisel young nobleman, F.
   damoiseau; fr. LL. domicella, dominicella, fem., domicellus,
   dominicellus, masc., dim. fr. L. domina, dominus. See Dame,
   and cf. Demoiselle, Doncella.]
   1. A young person, either male or female, of noble or gentle
      extraction; as, Damsel Pepin; Damsel Richard, Prince of
      Wales. [Obs.]
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   2. A young unmarried woman; a girl; a maiden.
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            With her train of damsels she was gone,
            In shady walks the scorching heat to shun. --Dryden.
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            Sometimes a troop of damsels glad, . . .
            Goes by to towered Camelot.           --Tennyson.
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   3. (Milling) An attachment to a millstone spindle for shaking
      the hopper.
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WordNet (r) 3.0 (2006):

damsel
    n 1: a young unmarried woman [syn: damsel, demoiselle,
         damoiselle, damosel, damozel]