Definition of poikilotherm
: 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
poikilothermicplay \ˌpȯi-kə-lō-ˈthər-mik\ adjective
poikilotherm was our Word of the Day on 11/30/2006. Hear the podcast!
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."
Seen and Heard
What made you want to look up poikilotherm? Please tell us where you read or heard it (including the quote, if possible).