n. pl. fo·li·os
a. A large sheet of paper folded once in the middle, making two leaves or four pages of a book or manuscript.
b. A book or manuscript of the largest common size, usually about 38 centimeters (15 inches) in height, consisting of such folded sheets.
a. A leaf of a book numbered only on the front side.
b. A number on such a leaf.
c. A page number.
3. Law A specific number of words used as a unit for measuring the length of the text of a legal document.
tr.v. fo·li·oed, fo·li·o·ing, fo·li·os
To number consecutively the pages or leaves of (a book, for example).
[Middle English, from Late Latin foliō, ablative of folium, leaf of paper, from Latin, leaf; see bhel-3 in the Appendix of Indo-European roots.]
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