The term pupa refers to the intermediate stage of an insect's life cycle between the larva and adult stages. The pupa is also known as a CHRYSALIS, which is a nine-letter word that can be found in crossword puzzles. During this stage, the insect undergoes metamorphosis, which is a process of transformation from one form to another. During this time, the pupa is encased in a protective shell or cocoon, and the insect's body undergoes dramatic changes until it emerges as an adult.