: a genus of extinct giant pigs (family Entelodontidae) of the Lower Miocene of Nebraska some of which exceed the modern bison in size
borrowed from New Latin, from dino-dino- + -hyus (as in Hippohyus, a pig genus known from Miocene fossils of South Asia, from hippo-hippo- + -hyus, a thematized combining form based on Greek hûs "wild or domestic hog")
Name introduced by the American paleontologist Olof August Peterson (1865-1933) in Science, New Series, vol. 22, No. 570 (December 1, 1905), p. 719, in a letter to the journal entitled "A correction of the generic name (Dinochœrus) given to certain fossil remains from the Loup Fork Miocene of Nebraska." In the letter Peterson proposes Dinohyus as a replacement for the name Dinochœrus, which he had given to the animal in an earlier issue (vol. 22, no. 555, August 18, 1905, pp. 211-12), on the grounds that Dinochœrus had already been employed taxonomically. According to the letter, the name Dinohyus had originally occurred to him, but he acceded to the suggestion of William J. Holland (the director of the Carnegie Museum of Natural History in Pittsburgh) that Dinochœrus would be preferable. Holland was unaware at the time that Dinochœrus was occupied. Peterson gave the animal the specific epithet hollandi in honor of Holland.
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