Bundle of Folded Pages, Sewn Together for a Book
Puzzle 17 of Life of a Book Medium Pack
Question is: Bundle of Folded Pages, Sewn Together for a Book
and the answer is: SIGNATURE
Word Meaning:
SIGNATURE — A person's name, written by that person, used as identification or to signify approval of accompanying material, such as a legal contract.
Definitions from Wiktionary.