forty-eightmo

[ fawr-tee-eyt-moh ]
/ ˈfɔr tiˈeɪt moʊ /

noun, plural for·ty-eight·mos for 2.

a book size of about 2½ × 4 inches (6 × 10 cm), determined by printing on sheets folded to form 48 leaves or 96 pages. Abbreviation: 48mo, 48°
a book of this size.

adjective

in forty-eightmo.

Origin of forty-eightmo

First recorded in 1885–90; forty-eight + -mo