brumation

Brumation is a specialized biological term used specifically for ectotherms, such as reptiles and amphibians. It is frequently confused with hibernation, but the two are physiologically distinct; while hibernation occurs in endotherms (mammals) to conserve energy through a drop in body temperature, brumation is a response to external environmental temperature drops that slow the animal's metabolism.

In a technical or veterinary context, the term describes a state of lethargy and decreased appetite rather than a deep sleep. Because it is a scientific term, it is rarely used in casual conversation unless discussing herpetology or pet reptile care.