The stages (they vary in number according to species of insect) of growth between molts of an insect nymph. Instars mostly look like little adults with minor variations. They molt as they grow but maintain the same basic body form. The instar stages are when the insect does all its growing. Insects have exoskeletons and can't grow unless they shed their old skin for a new one.

Contrast with metamorphosis.

In*star" (?), v. t.

To stud as with stars.

[R.] "A golden throne instarred with gems."

J. Barlow.

 

© Webster 1913.