Source : Webster's Revised Unabridged Dictionary (1913)

Poikilothermal \Poi`ki*lo*ther"mal\ (-th[~e]r"mal),
Poikilothermic \Poi`ki*lo*ther"mic\ (-th[~e]r"m[i^]k), a. [Gr.
   poiki`los changeable + E. thermal, thermic.] (Physiol.)
   Having a varying body temperature. See {Homoiothermal}.

Source : WordNet®

poikilothermic
     adj : of animals except birds and mammals; having body temperature
           that varies with the environment [syn: {poikilothermous},
            {heterothermic}, {ectothermic}]