18 mo
Variant of octodecimo
octodecimo
Definition
octo·deci·mo (äk′tō des′ə mō′)
noun pl. octodecimos -·mos′
- a page size (about 4 by 6 in), of a printer's sheet
- a book with pages of this size
Etymology: < L (in) octodecimo, (in) eighteen, abl. of octodecimus, eighteenth
adjective
with pages of this size
