Definition of "duckbilled"

The third group of mammals, the monotremes, claims a measly three distinct animals, and all are indigenous to Australia and New Guinea: the duckbilled platypus and the long-beaked and short-beaked echidnas, also known as spiny anteaters.

2008 May 13, Natalie Angier, “A Gene Map for the Cute Side of the Family”, in New York Times‎

The duckbilled dinosaurs (hadrosaurs) had broad, ducklike beaks. They walked or ran on their hind legs, and leaned down on their shorter front legs to graze on vegetation.

2005, Carson Creagh, Simone Ende, Angela Milner, Dinosaurs