A chrysalis is the hard protective shell that a caterpillar forms around itself while it transforms into a butterfly or moth. Inside this remarkable case, the caterpillar's body completely reorganizes: it breaks down into a kind of cellular soup and rebuilds itself with wings, compound eyes, and a totally different body structure. The chrysalis looks like a small pod hanging from a branch or leaf, often in shades of green, brown, or gold.

The transformation inside takes anywhere from a few days to several months, depending on the species. When the butterfly is ready, the chrysalis splits open and the new insect emerges, wet and crumpled. It pumps fluid into its wings to expand them, waits for them to dry and harden, and then flies away, looking nothing like the crawling creature that entered the chrysalis before.

People sometimes use chrysalis as a metaphor for any period of dramatic personal change. Someone might say they emerged from a chrysalis of shyness to become more confident, or that summer camp was a chrysalis where they discovered new interests. The word captures that sense of hidden transformation: you go in as one thing and come out as something completely different.