variation

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

• noun The act, fact, or process of varying.
• noun The extent or degree to which something varies.
• noun Something different from another of the same type: synonym: difference.
• noun Magnetic declination.
• noun Biology The existence within a species or other group of organisms of differences in form, function, or behavior, especially when hereditary.
• noun Mathematics A function that relates the values of one variable to those of other variables.
• noun A form that is an altered version of a given theme, diverging from it by melodic ornamentation and by changes in harmony, rhythm, or key.
• noun One of a series of forms based on a single theme.
• noun A solo dance, especially one forming part of a larger work.

from The Century Dictionary.

• noun The difference of offspring from the parent.
• noun Statistical or formal abnormality in living beings, or the departure of individual organisms from the mean, average, or rule for the race, considered as a fixed standard or logical species which individual animals approach or from which they recede.
• noun A change in a living being which is dne to its own activity as an individual, as contrasted with a change which is inherited. See the extract.
• noun A congenital or germinal change in a living being, which is not due to its own activity and is transmitted to descendants, as contrasted with a change which comes about in it by its own activity and is not transmitted to descendants.
• noun A change that may take place in an individual or a variety or species when its habitat changes.
• noun The amount of change which a quantity suffers in an hour: as, the hourly variation of the sun's declination.
• noun Variation which arises during the larval and later stages of development, as contrasted with variation which arises during the early embryonic stages.
• noun The act or process of varying; partial change in form, position, state, or qualities; alteration; mutation; diversity; variance; modification: as, variations of color; the slow variation of language.
• noun The extent to which a thing varies; the degree, interval, or amount of departure from a former condition, position, or relation; amount or rate of change: as, a variation of two degrees; a variation of twopence in the pound.
• noun Difference.
• noun Variance; dissension; discord.
• noun In grammar, change of form of words, as in declension, conjugation, etc.; inflection.
• noun In astronomy, any deviation from the mean orbit or mean motion of a heavenly body, occasioned by another disturbing body.
• noun In physics and navigation, the deviation of a magnetic needle from the true north, denoted by the angle which the vertical plane passing through the poles of the needle freely suspended, and undisturbed by local attraction, makes with the geographical meridian of the place: generally and more properly called declination.
• noun In biology, the act, process, or result of deviation from a given type of form or structure in a plastic vegetable or animal organization, by means of natural selection; or the sum of the phenomena resulting from the influence of conditions of environment, as opposed to those which would have been exhibited had the law of heredity alone been operative. See variability, 2, and variety, 6.
• noun In music, a tune or theme repeated with changes, elaborations, or embellishments, especially when made one of a series of movements aiming to develop the capacities of a given subject.
• noun In the calculus, an infinitesimal increment of a function, due to changes in the values of the constants, and affecting it, therefore, in different amounts for different values of the variables.
• noun In algebra: The following of a + sign after a—sign, or vice versa, in a row of signs.
• noun A linear arrangement of some of a given set of objects or of all. Thus, there are fifteen variations of the letters A, B, C, as follows: A, B, C, AB, BA, BC, CB, CA, AC, ABC, BCA, CAB, CBA, BAC, ACB.

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

• noun The act of varying; a partial change in the form, position, state, or qualities of a thing; modification; alteration; mutation; diversity; deviation
• noun Extent to which a thing varies; amount of departure from a position or state; amount or rate of change.
• noun (Gram.) Change of termination of words, as in declension, conjugation, derivation, etc.
• noun (Mus.) Repetition of a theme or melody with fanciful embellishments or modifications, in time, tune, or harmony, or sometimes change of key; the presentation of a musical thought in new and varied aspects, yet so that the essential features of the original shall still preserve their identity.
• noun (Alg.) One of the different arrangements which can be made of any number of quantities taking a certain number of them together.
• noun (Astron.) the yearly change in the right ascension or declination of a star, produced by the combined effects of the precession of the equinoxes and the proper motion of the star.
• noun See under Calculus.
• noun See under Compass.
• noun (Astron.) an inequality of the moon's motion, depending on the angular distance of the moon from the sun. It is greater at the octants, and zero at the quadratures.
• noun (Geog. & Naut.) the angle included between the true and magnetic meridians of a place; the deviation of the direction of a magnetic needle from the true north and south line; -- called also declination of the needle.

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

• noun The act or state of varying; a partial change in the form, position, state, or qualities of a thing; modification; alternation; mutation; diversity; deviation; as, a variation of color in different lights; a variation in size; variation of language.
• noun A related but distinct thing.
• noun nautical The angular difference at the vessel between the direction of true north and magnetic north. Also called magnetic declination.
• noun board games a line of play that differs from the original
• noun music a technique where material is repeated with alterations to the melody, harmony, rhythm, timbre, texture, counterpoint or orchestration.

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

• noun an artifact that deviates from a norm or standard
• noun an activity that varies from a norm or standard
• noun the angle (at a particular location) between magnetic north and true north
• noun a repetition of a musical theme in which it is modified or embellished