Glossary of Book and Ephemera Terms and Abbreviations
Part B. Size Terms
Listed here from large to small. These terms are often used to indicate the approximate size of a used book.
Please note: These terms are centuries old, and formerly referred to the number of [leaves] per [signature]. Today they mainly indicate height, and normally refer to normal, rectangular books that are taller than they are wide. Books that are wider than they are tall are called [oblong] and their heights may also be indicated with one of these terms.
folio. very oversized book, about 22 x 32 cm to about 25 x 37 cm (9" x 13" to about 10" x 15"). Larger
sizes occur: the 50 cm tall (20") baby elephant folio, 57 cm (23") elephant folio, 63 cm (25") atlas folio,
and 125 cm (50") double elephant folio. Originally, to make a folio, each large sheet of paper was folded
once to make two [leaves].
quarto / 4to. oversized book, about 20 x 27 cm to about 25 x 30 cm (8" x 11" to about 9" x 12"), between [octavo] and [folio] in size. Originally, to make a quarto, each large sheet of paper was folded twice to make four [leaves].
sm4to. small 4to, about 20 x 27 cm (8" x 11") rather than 22 x 30 cm (9" x 12").
octavo / 8vo. standard size, about 15 x 22 cm to about 17 x 25 cm (6" x 9" to about 7" x 10"); the most common size for current [hardcover] books. Originally, to make an octavo, each large sheet of paper was folded three times to make eight [leaves]. Pronounced ock-TAH-voh, or sometimes "eight-vo."
sm8vo. small 8vo, about 15 x 22 cm (6" x 9") rather than 17 x 25 cm (7" x 10").
12mo / twelvemo. small standard size, about 10 x 17 cm to about 12 x 20 cm (4" x 7" to about 5" x 8"); the most common size for [mass market paperbacks], and also some small [hardcovers]. Originally, to make a 12mo, each large sheet of paper was folded to make twelve [leaves]. Also called duodecimo.
16mo / sixteenmo. small, about 10 x 15 cm (4 x 6"), and no taller than 17 cm (6 3/4"). Some [mass market paperbacks] of the 1940s and 1950s are of this size. Originally each [signature] contained 16 [leaves]. Also called sextodecimo.
24mo / twentyfourmo. very small, about 7 x 12 cm (3 x 5"), and no taller than 14 cm (5 3/4"). Originally 24 [leaves] per [signature]. Also called vicesimo-quarto.
32mo / thirtytwomo. very small, about 5 x 10 cm (2 x 4"), and no taller than 10.5 cm (4 3/4"). Originally 32 [leaves] per [signature]. Also called tricesimo-secundo.
48mo. extremely small, no taller than 9.4 cm (3 3/4").
64mo. extremely small, no taller than 6.9 cm (2 3/4").
miniature. tiny, no more than 5 cm high (2"). Some miniature collectors accept books up to 7.5 cm high (3"). These were popular collector's items in the 1800s.
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N ~ O ~ P ~ Q ~ R ~ S ~ T ~ U ~ V ~ W ~ XYZ
This glossary was written and compiled by Gwen Foss of Alan's Used Books with thanks to the many independent bookdealers of TomFolio.com.