1. a toothed aquatic bird of the extinct genus Hesperornis, fossils of which are found in rocks of Cretaceous age in Kansas, having the rear legs modified for swimming and reaching a length of more than 4 feet (1.2 meters).

Origin of hesperornis

< New Latin (1872) < Greek Hésper(os) Hesperus + órnis bird
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for hesperornis

Historical Examples of hesperornis

  • This order includes only an extinct N. American bird Hesperornis.

    The Vertebrate Skeleton

    Sidney H. Reynolds

  • They've named him the "Hesperornis," which means "western bird."

  • The less numerous Hesperornis group were large and powerful divers.

  • They crept on all fours, they climbed with fingers and toes, they dived headlong, and swam as skilfully as any Hesperornis of old.

    Jungle Peace

    William Beebe

  • They are of two leading types, of which the Ichthyornis and Hesperornis are the standard specimens.