Not Cap or Hat but Casque

Many writers describe the chameleon's head crest as a cap or hat: some do it often, and others copy the same mistake. Once this wrong term spreads, both hobbyists and even scientists start repeating it, turning a precise anatomical feature into a fashion accessory. It must be corrected.

A cap or hat is a separate, wearable object—a covering placed on the head.

A casque, by contrast, is part of the skull itself: a bony, raised structure formed by the parietal and occipital plates. It is not worn, not removable, and not made of fabric or keratin like a helmet crest.

In chameleons, the casque defines species identity and sexual dimorphism. It varies in height, slope, and ornamentation, but it is always a skeletal formation—never a "hat."

Calling it a cap trivializes anatomy and misleads readers about its biological origin.

For scientific precision, every mention of a chameleon's head crest should use casque—the correct term for this remarkable cranial architecture.