demy

UK: /dɪˈmaɪ/ US: (di mī′)

WordReference Random House Unabridged Dictionary of American English © 2026

de•my  (di mī′), n., pl. -mies. 

1. a foundation scholar at Magdalen College, Oxford: so called because such a scholar originally received half the allowance of a fellow.
2. (in England) a size of printing paper, 17½ × 22½ in. (44 × 57 cm).
3. a size of drawing or writing paper, 15½ (39 cm) or 15 × 20 in. (38 × 51 cm) in England, 16 × 21 in. (41 × 53 cm) in the U.S.
4. Printing Also called demy′ octa′vo. a size of book, about 5½ × 8³⁄₄ in. (14 × 48 cm), untrimmed. Abbr.: demy 8vo
5. Printing Also called demy′ quar′to. [Chiefly Brit.] a size of book, about 8³⁄₄ × 11 in. (22 × 28 cm), untrimmed. Abbr.: demy 4to

• 1400–50; late Middle English demi, demy; see demi-

Collins Concise English Dictionary © HarperCollins Publishers::

demy / dɪˈmaɪ/ noun ( -mies)

1. a size of printing paper, 17 by 22 inches (444.5 × 571.5 mm)
2. a size of writing paper, 15 by 20 inches (Brit) (393.7 × 508 mm) or 16 by 21 inches (US) (406.4 × 533.4 mm)

Etymology: 16th Century: see demi-