tro·​chus | \ ˈtrōkəs \

Definition of trochus

1a capitalized : a genus of chiefly Old World tropical marine gastropods (family Trochidae) with beautifully nacreous bluntly conical shells including a large Indo-Pacific species (T. niloticus) extensively used in making buttons and ornamental objects
b plural -es : top shell
2 plural trochi\ -​ōˌkī \ or trochuses : the inner preoral band of cilia of a trochal disc broadly : trochal disc

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History and Etymology for trochus

New Latin, from Latin, wheel, iron hoop, from Greek trochos wheel

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“Trochus.” Dictionary, Merriam-Webster, Accessed 25 Feb. 2021.

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