paedomorphosis
definition
the retention of juvenile features in the adult stage of an organism
example
The phenomenon of paedomorphosis in certain amphibians allows them to retain larval characteristics, such as gills, even in their adult form.
synonyms
juvenilismneotenyjuvenile retention
word origin — from Greek 'paidos' meaning 'child' and 'morphosis' meaning 'formation' or 'shape'