[twen-tee-fawr-moh, -fohr-, twuhn-]
noun, plural twen·ty-four·mos.
a book size of about 3 5/8 × 5 1/8 inches (9 × 13 cm), determined by printing on sheets folded to form 24 leaves or 48 pages.
a book of this size. Symbol: 24mo, 24°
Origin of twenty-fourmo
Also called vigesimoquarto.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019