Definition of "twelvemo" [twelve•mo]

• See duodecimo. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Quiz, illustrated by Phiz, and published in one volume, square twelvemo."
• "Dedicator is humbly of opinion that so many libels, upon your Honourable sex, were never contained in any previously published work, in twelvemo or any other mo."
• "An ordinary twelvemo book, without illustrations in the text, is usually printed in forms of thirty-two pages, on what is known as a single-cylinder flat-bed press, which prints only one side of the paper at an impression."