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hyolithid

American  
[hahy-ol-i-thid] / haɪˈɒl ɪ θɪd /

noun

  1. any invertebrate of the extinct genus Hyolithes, most common in the Cambrian Period, having a limy, univalve shell, and thought to be related to the pteropods.


adjective

  1. belonging or pertaining to Hyolithes.

Etymology

Origin of hyolithid

< New Latin Hyolith ( es ) ( hyoid, -lith ) + -id 2