directory

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A book containing an alphabetical or classified listing of names, addresses, and other data, such as telephone numbers, of specific persons, groups, or firms.
• noun Computers An organizational unit for files that reside on a hard disk or other storage device.
• noun A book of rules or directions.
• noun A group or body of directors.
• adjective Serving to direct.

from The Century Dictionary.

• Guiding or directing; directive.
• noun A guide; a rule to direct; particularly (ecclesiastical), a book of directions for saying the various church offices and for finding the changes in them required by the calendar; especially, in medieval English usage, a book of directions for saying the hours. Also called ordinal, pica, or pie. The directory of the Greek Church is called the typicum.
• noun Specifically A book containing an alphabetical list of the inhabitants of a city, town, district, or the like, with their occupation, place of business, and abode.
• noun A board of directors; a directorate. Specifically
• noun [capitalized] The body constituting the executive in France during a part of the revolutionary epoch, consisting of five members called directors, one of whom retired each year.

from the GNU version of the Collaborative International Dictionary of English.

• adjective Containing directions; enjoining; instructing; directorial.
• noun A collection or body of directions, rules, or ordinances; esp., a book of directions for the conduct of worship.
• noun A book containing the names and residences of the inhabitants of any place, or of classes of them; an address book.
• noun A body of directors; board of management; especially, a committee which held executive power in France under the first republic.
• noun rare Direction; guide.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A list of names, addresses etc., of specific classes of people or organizations, often in alphabetical order or in some classification.
• noun computing A structured listing of the names and characteristics of the files on a storage device.
• noun computing A virtual container in a computer's file system, in which files and other directories may be stored. The files and subdirectories in a directory are usually related.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an alphabetical list of names and addresses
• noun (computer science) a listing of the files stored in memory (usually on a hard disk)