index

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Something that serves to guide, point out, or otherwise facilitate reference, especially:
2. n. An alphabetized list of names, places, and subjects treated in a printed work, giving the page or pages on which each item is mentioned.
3. n. A thumb index.
4. n. A table, file, or catalog.
5. n. Computer Science A list of keywords associated with a record or document, used especially as an aid in searching for information.
6. n. Something that reveals or indicates; a sign: "Her face . . . was a fair index to her disposition” ( Samuel Butler).
7. n. A character (☞) used in printing to call attention to a particular paragraph or section. Also called fist, hand.
8. n. An indicator or pointer, as on a scientific instrument.
9. n. Mathematics A number or symbol, often written as a subscript or superscript to a mathematical expression, that indicates an operation to be performed, an ordering relation, or a use of the associated expression.
10. n. A number derived from a formula, used to characterize a set of data.
11. n. A number that represents the change in price or value of an aggregate of goods, services, wages, or other measurable quantity in comparison with a reference number for a previous period of time.
12. n. Roman Catholic Church A list formerly published by Church authority, restricting or forbidding the reading of certain books.
13. v. To furnish with an index: index a book.
14. v. To enter in an index.
15. v. To indicate or signal.
16. v. To adjust through indexation.

Century Dictionary and Cyclopedia

1. n. That which points out; anything that shows, indicates, or manifests.
2. n. In logic, a sign which signifies its object by virtue of being really connected with it. Demonstrative and relative pronouns are nearly pure indices, because they denote things without describing them; so are the letters on a geometrical diagram, and the subscript numbers which in algebra distinguish one value from another without showing what those values are.
3. n. Something intended to point out, guide, or direct, as the hand of a clock or a steam-gage, the style of a sun-dial, an arm of a guide-post, or the figure of a hand .
4. n. A detailed alphabetic (or, rarely, classified) list or table of the topics, names of persons, places, etc., treated or mentioned in a book or a series of books, pointing out their exact positions in the volume.
5. n. Prelude; prologue.
6. n. In anatomy, the forefinger or pointing finger.
7. n. In ornithology, the principal or middle digit of the wing of a bird: so called by those who hold that it is homologous with the forefinger of a mammal; by those who hold that the middle digit of the wing is the middle digit of a mammal, the pollex or thumb of a bird's wing is called the index.
8. n. In mathematics, the figure or letter which shows to what power a quantity is involved; the exponent. In the theory of numbers the index of a number to a given base for a given prime modulus of which that base is a prime root is the index of the power of the base which is congruous to the number. (See exponent, 3.) The index-law is the principle that aa = adjective The word index is, besides, used in various special senses in mathematics. See phrases below.
9. n. In crystallography, in the notation of Whewell and Miller, one of three whole numbers which define the position of a face of a crystal: in the notation of Bravais, four numbers constitute the indices of a face of a hexagonal crystal.
10. n. In musical notation, a direct.
11. n. [capitalized] Same as Index Expurgatorius.
12. n. See craniometry.
13. To point out, as an index; indicate.
14. To make an index to, or place in an index: as, to index a book, or the contents of a book.
15. n. In instruments having graduated circles for angular measurement, the pointer or mark on the movable arm which is so placed as to move in close proximity to the graduated circle and thus to indicate the angle passed over between any two given positions of the arm; also, the arm or revolving member pivoted at the center of the graduated circle, which carries the index-mark or pointer.
16. n. The numerical value of a measured object or process, or of a counted phenomenon, expressed in percentage of another measured object, or process, or counted phenomenon: applied particularly in measurements of organisms for expressing the ratio between the sizes of two organs. See craniometry.
17. n. In forestry, the highest average actually found upon a given locality.
18. n. Same as palatomaxillary or palatoalveolar index. Turner.

Wiktionary

1. n. An alphabetical listing of items and their location; for example, the index of a book lists words or expressions and the pages of the book upon which they are to be found.
2. n. The index finger, the forefinger, or other pointer.
3. n. A sign; an indication; a token.
4. n. linguistics A type of noun where the meaning of the form changes with respect to the context. E.g., 'Today's newspaper' is an indexical form since its referent will differ depending on the context. See also icon and symbol.
5. n. economics A single number calculated from an array of prices or of quantities.
6. n. sciences A number representing a property or ratio, a coefficient.
7. n. mathematics A raised suffix indicating a power.
8. n. programming, computing An integer or other key indicating the location of data e.g. within a vector, database table, associative array, or hash table.
9. n. computing, databases A data structure that improves the performance of operations on a table.
10. v. transitive To arrange an index for something, especially a long text.
11. v. To inventory, to take stock.

GNU Webster's 1913

1. n. That which points out; that which shows, indicates, manifests, or discloses.
2. n. (printing) That which guides, points out, informs, or directs; a pointer or a hand that directs to anything, as the hand of a watch, a movable finger or other form of pointer on a gauge, scale, or other graduated instrument. a sign [☞] (called also fist) used to direct particular attention to a note or paragraph.
3. n. A table for facilitating reference to topics, names, and the like, in a book, usually giving the page on which a particular word or topic may be found; -- usually alphabetical in arrangement, and printed at the end of the volume. Typically found only in non-fiction books.
4. n. obsolete A prologue indicating what follows.
5. n. (Anat.) The second finger, that next to the pollex (thumb), in the manus, or hand; the forefinger; index finger.
6. n. (Math.) The figure or letter which shows the power or root of a quantity; the exponent.
7. n. The ratio, or formula expressing the ratio, of one dimension of a thing to another dimension.
8. n. A number providing a measure of some quantity derived by a formula, usually a form of averaging, from multiple quantities; -- used mostly in economics. See, for example, the consumer price index.
9. n. (computers) A file containing a table with the addresses of data items, arranged for rapid and convenient search for the addresses.
10. n. (computers) A number which serves as a label for a data item and also represents the address of a data item within a table or array.
11. n. (R. C. Ch.) The Index prohibitorius, a catalogue of books which are forbidden by the church to be read; also called Index of forbidden books and Index Librorum Prohibitorum.
12. v. To provide with an index or table of references; to put into an index.
13. v. (Economics) To adjust (wages, prices, taxes, etc.) automatically so as to compensate for changes in prices, usually as measured by the consumer price index or other economic measure. Its purpose is usually to copensate for inflation.
14. v. To insert (a word, name, file folder, etc.) into an index or into an indexed arrangement.

WordNet 3.0

1. n. the finger next to the thumb
2. v. list in an index
3. v. adjust through indexation
4. n. a mathematical notation indicating the number of times a quantity is multiplied by itself
5. v. provide with an index
6. n. a numerical scale used to compare variables with one another or with some reference number
7. n. an alphabetical listing of names and topics along with page numbers where they are discussed
8. n. a number or ratio (a value on a scale of measurement) derived from a series of observed facts; can reveal relative changes as a function of time