Dipnoi

noun

1. bony fishes of the southern hemisphere that breathe by a modified air bladder as well as gills; sometimes classified as an order of Crossopterygii

   noun.animal

   Synonyms subclass dipnoi

   Source: WordNet 3.0

2. A group of ganoid fishes, including the living genera <i>Ceratodus</i> and <i>Lepidosiren</i>, which present the closest approximation to the Amphibia. The air bladder acts as a lung, and the nostrils open inside the mouth. See <u>Ceratodus</u>, and <i>Illustration</i> in Appendix.

   noun

   Source: webster1913