Definitions
American Heritage® Dictionary of the English Language, Fourth Edition
- n. 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.
- n. A book composed of octavo pages.
Century Dictionary and Cyclopedia
- Having eight leaves to a sheet; formed of sheets of paper so folded as to make eight leaves to the sheet: as, an octavo volume.
- n. A book or pamphlet every section or gathering of which contains eight leaves, each leaf supposed to be one eighth of the sheet printed: usually written 8vo. When the name of the paper of which the book is made is not specified, an octavo is understood as a medium octavo, 6 × 9½ inches. Smaller octavos are — post 8vo, 5½ × 8½ inches; demy 8vo, 5¼ × 8 inches; crown 8vo, 5 × 7½ inches; cap 8vo, 4¼, × 7 inches. Larger octavos are — royal 8vo, 6½ × 10 inches; superroyal 8vo, 7 × 11 inches; imperial 8vo, 8¼ × 11½ inches. These are regular octavo folds of established sizes of paper in the United States. Publishers and booksellers describe as octavos only those books or leaves that are larger than 5½ × 8 and smaller than 7½ × 11½ inches, irrespective of the number of leaves in a section, which may be twelve or sixteen on thin paper and four or six on thick paper. Larger sizes are described as 4to, smaller sizes as 12mo or 16mo. Bibliographers, as a rule, limit the use of the word octavo to books having sections of eight leaves or sixteen pages.
- n. A sheet of paper evenly folded to make eight leaves and sixteen pages.
- n. A form of type containing eight pages.
Wiktionary
- n. paper, printing A sheet of paper 7 to 10 inches high and 4.5 to 6 inches wide, the size varying with the large original sheet used to create it. Made by folding the original sheet three times to produce eight leaves.
- n. printing A book of octavo pages.
GNU Webster's 1913
- n. A book composed of sheets each of which is folded into eight leaves; hence, indicating more or less definitely a size of book so made; -- usually written 8vo or 8°.
- adj. Having eight leaves to a sheet
WordNet 3.0
- n. the size of a book whose pages are made by folding a sheet of paper three times to form eight leaves
Etymologies
- Medieval Latin (in) octāvō, (in) an eighth, from Latin, ablative sing. of octāvus, eighth, from octō, eight. (American Heritage® Dictionary of the English Language, Fourth Edition)
Examples
“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”
“Two professed Lives of Mahomet have been composed by Dr. Prideaux (Life of Mahomet, seventh edition, London, 1718, in octavo) and the count de Boulainvilliers, (Vie de Mahomed, Londres, 1730, in octavo:) but the adverse wish of finding an impostor or a hero, has too often corrupted the learning of the doctor and the ingenuity of the count.”
“Poetry, (London, 1774, in octavo,) which was composed in the youth of that wonderful linguist.”
“Of the various petitions, apologies, &c., published by the princes of Courtenay, I have seen the three following, all in octavo: 1.”
“(Venezia, 1765, in octavo,) which represents the state and manners of Venice in the year 1008. 2.”
“A book of this kind is not larger than a thin octavo, and it maybe easily carried by your maid in her reticule without any parade, as, if it should not be wanted, it will be of very little incumbrance; whereas, if you have a table and the apparatus for drawing carried out, and should not happen to be visited by the pictorial muse, you will find it very disagreeable to be joked on so formidable a preparation having produced no result.”
The Lady's Country Companion: or, How to Enjoy a Country Life Rationally
“Philosophical Arrangements of Mr. James Harris, (London, 1775, in octavo,) who labored to revive the studies of Grecian literature and philosophy.] 60 Abulpharagius, Dynast.p. 81, 222.”
“The xivth letter of Tournefort (Voyage du Levont, tom.ii. p. 325 — 360, in octavo) describes what he had seen of the religion of the Turks.] * Such is Mahometanism beyond the precincts of the Holy City.”
Lists
These user-created lists contain the word ‘octavo’.
-
The Bindery
A list of bookbinding terms and phrases, for assembling new or repairing/reassembling old books.
perfect binding, animal glue, spine, textblock, polyvinyl acetate, double-fan adhesi..., board, backing, rounding, bone, book cloth, pasteboard and 270 more...
-
Logolepsy
"Luciferous Logolepsy is a collection of over 9,000 obscure English words. Though the definition of an 'English' word might seem to be straightforward, it is not. There exist so many adopted, deriv...
Anschauung, Areopagus, Argus, Briarean, Dei gratia, Dei judicium, Deo volente, Duecento, Foehn, Geflugelte Worte, Gegenschein, Hakenkreuz and 9230 more...
-
big book gre
abase, abbess, abbey, abbot, abdicate, abdomen, abdominal, abduction, abed, aberration, abet, abeyance and 6691 more...
-
Rare Books
Words used in the rare book trade (of which I was once a part). For more about how such books are put together, see hernesheir's excellent The Bindery.
foxing, gilt, headband, bumped, endpaper, leaf, colophon, vellum, laid paper, boards, device, engraving and 168 more...
-
spicolli's Words
terrapin, ravenous, fuck, sepulchral, garlic, suss, queer, curmudgeon, foodie, intricate, omphalos, subversion and 534 more...
-
Red Seas Under Red Skies
Words and phrase from Scott Lynch's book, Red Seas Under Red Skies.
legate, pugnacity, weevil, steady as a dry-d..., chit, sans, apprise, forfend, ken, expatriate, enclave, scrubs and 220 more...
-
persnickety parlance
behoove, ebullient, insouciant, insipient, froth, quandary, quixotic, tendril, maktub, furrow, furl, anastrophe and 1076 more...
-
Dead Trees and Friends
Paper, things you can do with paper, and other materials you can write on.
origami, codex, ephemera, folio, vellum, octavo, quarto, thermographic, decoupage, epistolary, palimpsest
-
College Reading Words
words i find in my reading at college
empirical, caprice, telos, insofar, bedeviled, nihilism, confound, nomenclature, negate, hegemony, ebb, homophily and 35 more...
-
bookish
grimoire, bildungsroman, roman a clef, chapbook, picaresque, codicology, epistolary, colophon, manuscript, memoir, incunabulum, bibliomaniac and 47 more...
Tweets
Looking for tweets for octavo.

reesetee Usually written as 8vo; the most common traditional book format, made from printed sheets folded three times, giving eight leaves (16 pages). Also used in a general way to indicate a book measuring about 7 x 10 inches.
Feb 20, 2007