An open telephone book.
telephone book definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a book in which are listed alphabetically the names of persons, businesses, etc. having telephones in a specified area, along with their addresses and telephone numbers
also telephone directory
telephone book definition by American Heritage Dictionary
A directory of the names of telephone subscribers with their telephone numbers and often their addresses.