ostracoderms

ostracoderm

[os-truh-koh-durm]
noun
any of several extinct jawless fishes of the Ordovician, Silurian, and Devonian periods, having the body enclosed in an armor of bony plates.

Origin:
1890–95; < Neo-Latin Ostracodermi, plural ofOstracodermus < Greek ostrakódermos with a shell, equivalent to óstrako(n) shell, tile + -dermos -derm

Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To ostracoderms
Collins
World English Dictionary
ostracoderm (ˈɒstrəkəˌdɜːm, ɒsˈtrækə-)
 
n
any extinct Palaeozoic fishlike jawless vertebrate of the group Ostracodermi, characterized by a heavily armoured body
 
[C19: via New Latin from Greek ostrakon shell + -derm]

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
American Heritage
Science Dictionary
ostracoderm   (ŏs'trə-kŏ-dûrm')  Pronunciation Key 
Any of three orders of small, 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).
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Related Words
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature