electronic equipment that converts sound into electrical signals that can be transmitted over distances and then converts received signals back into sounds; "I talked to him on the telephone"
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 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