noun or·nitho·rhyn·chus \ȯ(r)ˌnithəˈriŋkəs, ˌȯ(r)nəthōˈr-\

Definition of ornithorhynchus

  1. 1 capitalized :  a genus (coextensive with the family Ornithorhynchidae) of egg-laying mammals including only the platypus

  2. 2 plural -es :  platypus

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Origin and Etymology of ornithorhynchus

New Latin, from ornith- + -rhynchus

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