Homoiotherm

Part of speech: noun

Definitions

1. An entity that possesses the capability to sustain a stable internal temperature regardless of external temperature fluctuations
2. A living being that can control its body heat to remain constant in varying environmental temperatures
3. An organism that maintains a consistent internal thermal state despite changes in the surrounding environment temperature

Etymology: Homoiotherm is built from two Greek elements. "Homoios" means "similar" or "like", and "therme" means "heat", so the word literally describes an animal that keeps a similar temperature. The "-therm" ending is the same Greek root that gives us "thermometer" and "thermos", and the "homoio-" prefix appears in other scientific coinages where it signals sameness. The distinction the word draws is with cold-blooded animals. Creatures like reptiles and fish take on the temperature of their surroundings, while homoiotherms generate and regulate their own internal heat, keeping it relatively constant whatever the weather. That is why mammals and birds can stay active in cold conditions that leave a lizard sluggish. Because the term is a modern scientific construction from classical Greek parts, it reflects the classifying habits of naturalists rather than any everyday speech of the ancient Greeks. The spelling "homeotherm" is a common variant, with the same meaning and the same roots.

Synonyms: warm-blooded animal, endotherm, homeothermic organism, constant temperature animal, regulator

Antonyms: poikilotherm, cold-blooded animal, ectotherm, variable temperature organism, thermoregulatory