adj. cold-blooded: being unable to regulate the body temperature, which fluctuates according to that of the surroundings. Reptiles and amphibians are cold-blooded. Compare homoiothermic. —poikilothermy n.
adj. warm-blooded: able to maintain a constant body temperature independently of, and despite variations in, the temperature of the surroundings. Mammals (including humans) and birds are homoiothermic. Compare poikilothermic. —homoiothermy n.... homoiothermic
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