oc·ta·vo
noun/ɒkˈteɪvəʊ/, /ɒkˈtɑːvəʊ/
/ɑːkˈteɪvəʊ/, /ɑːkˈtɑːvəʊ/
(plural octavos)
(specialist)- a size of a book page that is made by folding each sheet of paper into eight leaves (= 16 pages)
八开本 Word Originlate 16th cent.: from Latin in octavo ‘in an eighth’, from octavus ‘eighth’.