Metamorphosis

A marked and more or less abrupt change in form or structure during the course of some development process. In biology this refers to the transition from one postembryonic developmental stage to another within a relatively short period of time (e.g. in insect development), or to the sum of the various modifications, whether phylogenetic or primarily ontogenetic through which a primitive plant structure may pass in the course of its development. It may also be used for the transformation of a musical figure or idea into a rhythmically or melodically altered repetition of the original, or the change of chemical compound into an isomeric form.