[1] : The Collaborative International Dictionary of English v.0.48

eighth \eighth\ =atth, a. as. eahtoetha.
   1. next in order after the seventh.
      1913 webster

   2. consisting of one of eight equal divisions of a thing.
      1913 webster

   eighth note mus., the eighth part of a whole note, or
      semibreve; a quaver.
      1913 webster
see also:
eighth note 

[2] : The Collaborative International Dictionary of English v.0.48

eighth \eighth\, n.
   1. the quotient of a unit divided by eight; one of eight
      equal parts; an eighth part.
      1913 webster

   2. mus. the interval of an octave.
      1913 webster

[3] : WordNet (r) 2.0

eighth
     adj : coming next after the seventh and just before the ninth in
           position syn: 8th
     n 1: position eight in a countable series of things
     2: an eighth part syn: one-eighth
see also:
8th one-eighth 

[4] : Moby Thesaurus II by Grady Ward, 1.0

27 moby thesaurus words for "eighth":
   contraoctave, double contraoctave, eightfold, four-foot octave,
   four-line octave, great octave, octadic, octagonal, octahedral,
   octal, octan, octaploid, octastyle, octave, octofid, octonary,
   octosyllabic, octuple, one-line octave, ottava, ottava alta,
   ottava bassa, small octave, subcontraoctave, tone row,
   two-foot octave, two-line octave

Eighth >> E Words
Eighth, definition of term: Eighth
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