The Collaborative International Dictionary of English v.0.48:

Hoiden \Hoi"den\, n. [OE. hoydon a lout, rustic, OD. heyden a
   heathen, gypsy, vagabond, D. heiden, fr. OD. heyde heath, D.
   heide. See Heathen, Heath.] [Written also hoyden.]
   1. A rude, clownish youth. [Obs.] --Milton.
      [1913 Webster]

   2. A rude, bold girl; a romp. --H. Kingsley.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Hoyden \Hoy"den\, n.
   Same as Hoiden.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hoyden
    n 1: a girl who behaves in a boyish manner [syn: tomboy,
         romp, hoyden]

Moby Thesaurus II by Grady Ward, 1.0:

54 Moby Thesaurus words for "hoyden":
   amazon, androgyne, babe, baby, broad, butch, chick, colleen, cutie,
   dame, damoiselle, damsel, demoiselle, doll, dyke, filly, frail,
   gal, gamine, girl, girlie, heifer, jeune fille, jill, junior miss,
   lass, lassie, lesbian, little missy, mademoiselle, maid, maiden,
   miss, missy, nymphet, piece, romp, schoolgirl, schoolmaid,
   schoolmiss, skirt, slip, subdeb, subdebutante, subteen, subteener,
   teenybopper, tomato, tomboy, virago, virgin, wench, young creature,
   young thing