duodecimo

Latin ablative of duodecimus (“twelfth”) (from duodecim 'twelve', from duo 'two' + decem 'ten')

duodecimo (plural duodecimos)

1. (paper, printing) A size of paper, so called because it is originally made by folding and cutting a single sheet from a printing press into 12 leaves; (5 by 7¾ inches): 6.5 to 7.5 inches high, approximately 4.5 inches wide.
2. A sheet or page of that size.
3. (printing) A book having pages of that size.
   • 2015, William Logan, “A Critics Notebook”, in Guilty Knowledge, Guilty Pleasure, page 304:

     In recent years, I have taken to reading while walking. I believe the Romantics were guilty of such behavior; a duodecimo was small enough to fit into a jacket pocket.

• (paper size): twelvemo, 12mo, 12º
• (book size): twelvemo, 12mo, 12º, D

English paper and book sizes

Latin	folio	quarto	sexto	octavo	duodecimo	sextodecimo	octodecimo	vicesimo-quarto	trigesimo-secundo	quadragesimo-octavo	sexagesimo-quarto
ALA	F	Q		O	D	S	T		Tt	Fe	Sf
height (cm)	> 30	25-30	25-30	20-25	17.5-20	15-17.5	12.5-15	12.5-15	10-12.5	7.5-10	< 7.5
printers'	folio	quarto	sixmo	octavo	twelvemo	sixteenmo	eighteenmo	twenty-fourmo	thirty-twomo	forty-eightmo	sixty-fourmo
abbrev.	fo or f	4to	6to or 6mo	8vo	12mo	16mo	18mo	24mo	32mo	48mo	64mo
abbrev.	2º	4º	6º	8º	12º	16º	18º	24º	32º	48º	64º
	<<   bigger       smaller   >>

Borrowed from Latin in duodecimō (“in a twelfth”), from duodecimus (“twelfth”).

• IPA^(key): /ˌdy.oːˈdeː.si.moː/

• Audio:

  (file)

• Hyphenation: duo‧de‧ci‧mo

duodecimo n (plural duodecimo's, diminutive duodecimootje n)

1. a size of paper, so called because it is originally made by folding and cutting a single sheet from a printing press into 12 leaves; (5 by 7¾ inches): 6.5 to 7.5 inches high, approximately 4.5 inches wide
2. a page of that size; hence, a whole book having pages of that size

From Latin duodecimus.

duodecimo (feminine duodecima, masculine plural duodecimi, feminine plural duodecime)

1. (literary) twelfth

   Synonyms: (old-fashioned) decimosecondo, dodicesimo

duodecimō

1. dative/ablative masculine/neuter singular of duodecimus