Yes, the process of a child changing into an adult can be metaphorically described as metamorphosis. This term typically refers to a significant transformation, and the transition from childhood to adulthood involves profound physical, emotional, and psychological changes. While metamorphosis is often associated with biological transformations in nature, such as a caterpillar becoming a butterfly, it can also aptly capture the complexities of human development.
Yes it is the same condition, as you have only changed the phosis to posis, Onchogryphosis is hypertrphy (overgrowth) of the nail with gross deformity of the nail. you may have mistaken Onuchophosis, which is a corn or callous in the nail sulci.