poikilotherm

(poi-kĭl'ə-thûrm')
n.
An organism, such as a fish or reptile, having a body temperature that varies with the temperature of its surroundings; an ectotherm.

[Greek poikilos, spotted, various + -THERM.]

poikilothermia poi'ki·lo·ther'mi·a (-thûr'mē-ə) n.
poikilothermic poi'ki·lo·ther'mic (-mĭk) adj.

An organism which has its body heat regulated by the temperature of its surroundings; poikilothermy is the state of being cold-blooded.

(poi'kə-lə-thûrm', poi-kĭl'ə-)
n.

An organism, such as a fish or reptile, having a body temperature that varies with the temperature of its surroundings; an ectotherm.

An animal that exhibits poikilothermy; a cold-blooded animal.

IN BRIEF: adj. - Of animals except birds and mammals.