a reference work (often in several volumes) containing articles on various topics (often arranged in alphabetical order) dealing with the entire range of human knowledge or with some particular specialty
a telephone directory or section of a directory (usually printed on yellow paper) where business products and services are listed alphabetically by field along with classified advertising
a book (or manuscript) consisting of large sheets of paper folded in the middle to make two leaves or four pages; "the first folio of Shakespeare's plays"