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
ˌpȯi-kə-lō-ˈthər-mik How to pronounce poikilotherm (audio)
adjective

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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

Theme music by Joshua Stamper ©2006 New Jerusalem Music/ASCAP

Dictionary Entries Near poikilotherm

poikiloblast

poikilotherm

poil

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Cite this Entry

“Poikilotherm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/poikilotherm. Accessed 1 Dec. 2024.

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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

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