noun

• (printing) A book size, corresponding to the page size.
• (paper) Abbreviation of octavo., a page size (5"-6.25" x 7.5"-10"). [(paper, printing) A sheet of paper 7 to 10 inches (= 17.78 to 25.4 cm) high and 4.5 to 6 inches (= 11.43 to 15.24 cm) wide, the size varying with the large original sheet used to create it. It is made by folding the original sheet three times to produce eight leaves.]