larva

n. early wingless stage of an insect (Entomology)

A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). The larva can look completely different from the adult form, for example, a caterpillar differs from a butterfly. Larvae often have special (larval) organs which do not occur in the adult form. The larvae of some species can become pubescent and not further develop into the adult form (for example, in some newts). This is called neoteny.
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Noun
1. the immature free-living form of most invertebrates and amphibians and fish which at hatching from the egg is fundamentally unlike its parent and must metamorphose
(hypernym) animal, animate being, beast, brute, creature, fauna
(hyponym) ascidian tadpole

n. larva, phantom, grub

n. larva, early wingless stage of an insect (Entomology); grub