Nouns

(n)paddlefish, duckbill, Polyodon spathulaprimitive fish of the Mississippi valley having a long paddle-shaped snout
(n)platypus, duckbill, duckbilled platypus, duck-billed platypus, Ornithorhynchus anatinussmall densely furred aquatic monotreme of Australia and Tasmania having a broad bill and tail and webbed feet; only species in the family Ornithorhynchidae

Adjectives

(s)duckbill, duck-billedhaving a beak resembling that of a duck“a duck-billed dinosaur”