octavo

from WordNet (r) 3.0 (2006)

octavo
    n 1: the size of a book whose pages are made by folding a sheet
         of paper three times to form eight leaves [syn: {octavo},
         {eightvo}, {8vo}]

from The Collaborative International Dictionary of English v.0.48

Octavo \Oc*ta"vo\, n.;pl. {Octavos}. [L. in octavo; in in +
   octavo, abl. of octavus. See {Octave}.]
   A book composed of sheets each of which is folded into eight
   leaves; hence, indicating more or less definitely a size of
   book so made; -- usually written 8vo or 8[deg].
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Octavo \Oc*ta"vo\, a.
   Having eight leaves to a sheet; as, an octavo form, book,
   leaf, size, etc.
   [1913 Webster]

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