Search Dictionary
Definition of placoderm

placoderm

/ˈplæk.əˌdɜːrm/
plac · o · derm

Plural:placoderms
•
Adjective:placodermal
JUMP TO:

placoderm Lexical Profile

placoderm Game Scores & Validity

• noun

1

An extinct jawed fish of the class Placodermi, prevalent during the Silurian and Devonian periods, characterized by a heavily armored head and thorax made of articulated bony plates.

Example

"Dunkleosteus is one of the most famous and formidable placoderms, known for its massive size and powerful, self-sharpening jaw plates."

• Rhymes for placoderm

Word Origin & Etymology

Coined in the mid-19th century from Greek 'plax' or 'plak-' (flat plate) and 'derma' (skin), referring to the protective bony plates covering the heads and thoraxes of these prehistoric fish.

Usage Trend

Historical frequency of usage in published text.

180019102020

Cite this Entry


Wordmom. (2026). Definition of Placoderm. In Wordmom Dictionary. Retrieved Oct 18, 2026, from https://wordmom.com/dictionary/placoderm
Wordmom is your complete guide to the English language. Whether you're looking up a definition, searching for the perfect synonym, or unscrambling letters for a word game, our comprehensive suite of tools is designed to help you find the right word, every time.
Dictionary & Reference
© 2016–2026 Wordmom Network. All rights reserved. Made with for word lovers everywhere.
Disclaimer: SCRABBLE®, Words With Friends®, Wordle®, and related game titles or tournament codes are registered trademarks of their respective owners (including Hasbro, Mattel, Zynga, The New York Times, NASPA, and WESPA). Wordmom is an independent reference utility for educational and entertainment purposes, not affiliated with, sponsored, or endorsed by these entities. All game names are referenced strictly under nominative fair use for compatibility.