1. poikilotherm - Noun
2. poikilotherm - Adjective
an animal whose body temperature varies with the temperature of its surroundings; any animal except birds and mammals
Source: WordNetThe lower proline and hydroxproline contents of cold-water fish and other poikilotherm animals leads to their collagen having a lower thermal stability than mammalian collagen. Source: Internet
Therefore, the great white shark can be considered an endothermic poikilotherm because its body temperature is not constant but is internally regulated. Source: Internet