Definition of "octavo" []

• The page size, from 5 by 8 inches to 6 by 9 1/2 inches, of a book composed of printer's sheets folded into eight leaves. (noun)
• A book composed of octavo pages. (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.

• "A customer is likely to ask for Ivanhoe in English, octavo, bound in leather."
• "In the seventh edition (1720) I find to my great solace and comfort the entry, dog, 'a well-known creature, 'a somewhat meagre definition, improved into 'a quadruped well-known' by Nathaniel Bailey, whose dictionary, first published in octavo (1721), ran through a very large number of editions and became the standard authority until superseded by Johnson."
• "XXXIX. of the third edition, in octavo; where it is likewise shown, that none of these parts which are deposited beneath the cuticle of the tree, is in itself"