poikilotherm

noun

poi·​ki·​lo·​therm pȯi-ˈkē-lə-ˌthərm How to pronounce poikilotherm (audio) -ˈki- How to pronounce poikilotherm (audio)
: an organism (such as a frog) with a variable body temperature that tends to fluctuate with and is similar to or slightly higher than the temperature of its environment : a cold-blooded organism
poikilothermic adjective

Did you know?

Poikilotherms are also called "ectotherms" or "cold-blooded animals." Such creatures are the thermoregulatory opposites of "endotherms" or "homeotherms" - better known to most of us as "warm-blooded animals" - which are able to maintain a fairly high and constant body temperature relatively independent of the temperature of the surroundings. "Stenotherms" are creatures that can survive only within a very narrow temperature range. The "-therm" in all of these terms comes from the Greek thermē, which means "heat."

Word History

Etymology

Greek poikilos variegated + International Scientific Vocabulary -therm — more at paint

First Known Use

1920, in the meaning defined above

Time Traveler
The first known use of poikilotherm was in 1920

Podcast

Dictionary Entries Near poikilotherm

Cite this Entry

“Poikilotherm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/poikilotherm. Accessed 24 Dec. 2024.

Kids Definition

poikilotherm

noun
poi·​ki·​lo·​therm pȯi-ˈkē-lə-ˌthərm How to pronounce poikilotherm (audio) -ˈkil-ə- How to pronounce poikilotherm (audio)
: an animal (as a frog) with a temperature that tends to change with and is similar to or slightly higher than the environment : a cold-blooded organism

Medical Definition

poikilotherm

noun
poi·​ki·​lo·​therm ˈpȯi-ki-lə-ˌthərm How to pronounce poikilotherm (audio) (ˌ)pȯi-ˈkil-ə- How to pronounce poikilotherm (audio)
: an organism (as a frog) with a variable body temperature that is usually slightly higher than the temperature of its environment : a cold-blooded organism

called also heterotherm

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!