n. That which points out; anything that shows, indicates, or manifests.n. In logic, a sign which signifies its object by virtue of being really connected with it.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 .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.n. Prelude; prologue.n. In anatomy, the forefinger or pointing finger.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.n. In mathematics, the figure or letter which shows to what power a quantity is involved; the exponent.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.n. In musical notation, a direct.n. [capitalized] Same as Index Expurgatorius.n. See craniometry.To point out, as an index; indicate.To make an index to, or place in an index: as, to index a book, or the contents of a book.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.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.n. In forestry, the highest average actually found upon a given locality.n. Same as palatomaxillary or palatoalveolar index. Turner.
