n. 1.an instance of change 2.an activity that varies from a norm or standard 3.a repetition of a musical theme in which it is modified or embellished 4.something a little different from others of the same type 5.an artifact that deviates from a norm or standard 6.the angle (at a particular location) between magnetic north and true north 7.(astronomy) any perturbation of the mean motion or orbit of a planet or satellite (especially a perturbation of the earth's moon) 8.(biology) an organism that has characteristics resulting from chromosomal alteration 9.(ballet) a solo dance or dance figure 10.the act of changing or altering something slightly but noticeably from the norm or standard