n. pl. oc·ta·vos 1. The page size, from 5 by 8 inches to 6 by 9.5 inches, of a book composed of printer's sheets folded into eight leaves. 2. A book composed of octavo pages. In both senses also called eightvo. [Medieval Latin (in) octāvō, (in) an eighth, from Latin, ablative sing. of octāvus, eighth, from octō, eight; see oktō(u) in the Appendix of Indo-European roots.] |
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