from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. See octodecimo.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. octodecimo (as a paper size in printing).

from the GNU version of the Collaborative International Dictionary of English

  • See octodecimo.

from The Century Dictionary and Cyclopedia

  • n. A size of book of which each signature is made up of 18 folded leaves, making 36 pages to the signature: commonly written 18mo.
  • Of the size of a sheet folded into eighteen leaves; consisting of such sheets: as, an eighteenmo page or book.


From 18mo, abbr. of octodecimo.
(American Heritage® Dictionary of the English Language, Fourth Edition)


Sorry, no example sentences found.


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