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Definition of ectothermic

Of or relating to an organism that regulates its body temperature largely by exchanging heat with its surrounding environment.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.


What does ectothermic mean?

Ectothermic describes an organism that regulates its internal temperature by exchanging heat with its surrounding environment.

Ectothermic organisms, or ectotherms, cannot produce heat on their own. They need heat from their environment to stay warm. For example, snakes are ectothermic. They will stay warm by laying on a warm rock or in the sunshine. Many types of amphibians, fish, and insects are also ectothermic.

Example: Because Vahe’s tortoise is ectothermic, he has to keep a heat light on it when the weather gets cool.

Where does ectothermic come from?

The first records of the term ectothermic come from around the 1940s. It combines the term ectotherm, meaning “a cold-blooded animal,” and the suffix -ic, which forms adjectives from nouns.

Along with ectothermic organisms, you might also hear about endothermic organisms, which create their own heat by consuming food. Some animals have properties of both endotherms and ectotherms and are sometimes called heterotherms. Bumblebees, for example, are ectothermic, but can create internal heat by rubbing their muscles against each other to generate friction.

You might hear cold-blooded for ectothermic and warm-blooded for endothermic. These are older terms that are used less often by scientists because they can be misleading. An ectothermic animal doesn’t necessarily have cold blood or isn’t necessarily cold. Instead, it’s just incapable of producing internal heat. Cold-blooded and warm-blooded are still used sometimes in casual conversations, but ectothermic and endothermic are the preferred scientific terms.

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What are some synonyms for ectothermic?

What are some words that share a root or word element with ectothermic

What are some words that often get used in discussing ectothermic?

What are some words ectothermic may be commonly confused with?

How is ectothermic used in real life?

Ectothermic is almost always used in scientific contexts.

Try using ectothermic!

Which of the following is a synonym for ectothermic?

A. endothermic
B. freezing
C. warm-blooded
D. cold-blooded