Neoteny is a term used to describe the retention of juvenile traits in adult animals. While the word itself may not be commonly known, there are many synonyms that can be used to describe this phenomenon. Some of these include youthful, child-like, immature and undeveloped. Others may use the term infantile, naive, or juvenile to describe neoteny. This unique trait is found in many different animals, including humans, and pertains to physical and behavioral characteristics. Regardless of the chosen synonym, it is clear that neoteny is a unique and fascinating phenomenon that allows adult animals to retain the traits of their youth.