Am-phĭp’nēüst, n.

noun

n. [Gr. ἀμφί, on both sides, about, and πνεύστης, one who breathes, from πνεῖν, to breathe.] (Zoöl.) One of a tribe of reptiles, which have both lungs and gills at the same time, as the proteus and siren. Brande.