Larva: (LAR-va) One of the phases in the life cycle of some insects, such as crabronid wasps and tachinid flies. See insect life cycle. Larva is the singular form of the word, and larvae (LAR-vee) is the plural form. (Newspaper reporters commonly, but wrongly, write about "a larvae"). Many insect larvae are very different in appearance from the adults. Insect larvae do not have wings. Insect larvae feed, and grow, and molt several times.