poikilothermism

or poi·ki·lo·ther·my

[ poi-kuh-loh-thur-miz-uhm, poi-kil-uh- ]

noun

, Zoology.

1. the state or quality of being cold-blooded, as fishes and reptiles.

Word History and Origins

Origin of poikilothermism¹

First recorded in 1900–05; from Greek poikilos “various” + therm- ( def ) + -ism ( def )