D defs.my
Entry 2 senses · 2 variants Webster, 1913

Duodecimo

· Du·o·dec·i·mo · IPA
01 a. Having twelve leaves to a sheet; as, a duodecimo from, book, leaf, size, etc.
  1. 1.
    Having twelve leaves to a sheet; as, a duodecimo from, book, leaf, size, etc.
02 n. A book consisting of sheets each of which is folded into twelve leaves; hence, indicating, more or less definitely, a size of a book; -- us…
pl. Duodecimos
  1. 1.
    A book consisting of sheets each of which is folded into twelve leaves; hence, indicating, more or less definitely, a size of a book; -- usually written 12mo or 12°.