octavo; 8vo
A book format where each sheet is folded into eight leaves (16 pages). Used in publishing and bibliography.
This book is in octavo format, a size that's easy to hold.
Old Bibles were often printed in octavo.
Standard spelling for this book format term.
Variant spelling; less common but still encountered.
Variant spelling; less common but still encountered.
From 八つ折り (yatsuori, 'folding into eight') + 判 (ban, 'format/size').