Capable of maintaining a relatively constant body temperature independent of the surrounding environment.(adjective)
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Use "homeothermic" in a sentence
"Moreover, they are truly homeothermic, requiring maintenance of a constant internal body temperature that is considerably above environmental temperature."
"While hibernation during the winter is found in a few arctic mammals such as the Arctic ground squirrel (Spermophilus parryii), most homeothermic animals are active throughout the year."
"Reptiles are poikilothermic, which means that they can not regulate heat internally (as opposed to birds and mammals which are homeothermic)."