met·a·mor·pho·sis
/ˌmedəˈmôrfəsəs/

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nounZOOLOGY
1 (in an insect or amphibian) the process of transformation from an immature form to an adult form in two or more distinct stages.
◦ a change of the form or nature of a thing or person into a completely different one, by natural or supernatural means.