Definitions

1. noun

A collection of sheets of paper, especially printed or written matter, bound together, typically in a large format.

“The library had an extensive collection of art folios from the 19th century.”

2. noun

A section of a book, especially one that contains music or illustrations, typically bound separately from the rest of the text.

“The folio section of the book contained beautiful watercolor illustrations.”

3. noun

A unit of measurement for book sizes, equivalent to 12 inches (30.5 cm) or more in height, typically containing 8-12 pages.

“The publisher printed the novel in a large folio edition.”