IPA: /ˌhoʊləˈmɛtəˌboʊləs/
KK: /hɑloʊˈmɛtəˌboʊləs/
Describing an organism that undergoes a complete transformation during its life cycle, including distinct stages such as egg, larva, pupa, and adult.
Butterflies are holometabolous insects, going through a complete metamorphosis from caterpillar to adult.
Holometabolous is formed from "holo-" (meaning whole or entire) and "metabolous" (from Greek "metabole", meaning change). The term describes insects that undergo a complete metamorphosis, involving distinct life stages: egg, larva, pupa, and adult, thus representing a whole or entire change in form.
Think of 'whole' ('holo-') and 'change' ('metabolous') to remember that holometabolous refers to insects that undergo a complete transformation in their life cycle.