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ostracoderm

American  
[os-truh-koh-durm] / ˈɒs trə koʊˌdɜrm /

noun

  1. any of several extinct jawless fishes of the Ordovician, Silurian, and Devonian periods, having the body enclosed in an armor of bony plates.


ostracoderm British  
/ ɒsˈtrækə-, ˈɒstrəkəˌdɜːm /

noun

  1. any extinct Palaeozoic fishlike jawless vertebrate of the group Ostracodermi, characterized by a heavily armoured body

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ostracoderm Scientific  
/ ŏstrə-kŏ-dûrm′ /
  1. Any of various extinct primitive jawless fishes of the Ordovician through the Devonian Period. Most ostracoderms had their heads or entire bodies encased in fused bony plates. Some or all ostracoderms are sometimes classified together with the modern cyclostomes (lampreys and hagfish).


Etymology

Origin of ostracoderm

1890–95; < New Latin Ostracodermi, plural of Ostracodermus < Greek ostrakódermos with a shell, equivalent to óstrako ( n ) shell, tile + -dermos -derm

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But in the oceans and along coastal areas, there would have been many species of trilobites and brachiopods; red and green algae; corals, as well as several species of ostracoderms, a jawless, armored Ordovician-era fish.

From Forbes

Some of the members of this order were, like the ostracoderms, cased in armor, but their higher rank is shown by their powerful jaws and by other structures.

From Project Gutenberg