8vo

book size of 6x9 inches; 6x9 inch book

Octavo (usually abbreviated 8vo, 8°, 8o, or Oct.) is a book size resulting from the use of standard size sheets of paper folded three times to make eight leaves. Each leaf is usually printed on each side, so this creates a signature of 16 pages in total. It was introduced by Aldus Manutius of Venice, when he produced Virgil's Opera in the octavo format, in 1501, in order to facilitate portable reading for men of leisure. The modern general use of the term refers to books which are between 8" and 10" (20-25 cm) tall, the most common size for modern hardbound books. More specific sizes can be denoted by:Foolscap octavo (6¾" by 4¼")Crown octavo (7½" by 5")Demy octavo (8¾" by 5⅝")Royal octavo (10" by 6¼")
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Noun
1. the size of a book whose pages are made by folding a sheet of paper three times to form eight leaves
(synonym) octavo, eightvo
(hypernym) size