Bible Dictionaries
Fol'io

Webster's Dictionary

(1):

(v. t.) To put a serial number on each folio or page of (a book); to page.

(2):

(a.) Formed of sheets each folded once, making two leaves, or four pages; as, a folio volume. See Folio, n., 3.

Bibliography Information
Webster, Noah. Entry for 'Fol'io'. Noah Webster's American Dictionary. https://www.studylight.org/​dictionaries/​eng/​web/​f/folio.html. 1828.