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[plas-truh n] /ˈplæs trən/
a piece of plate armor for the upper part of the torso in front.
Fencing. a quilted pad worn over part of the torso, for protection.
an ornamental front piece of a woman's bodice.
the starched front of a shirt.
Zoology. the ventral part of the shell of a turtle.
Origin of plastron
1500-10; < Middle French < Italian piastrone, augmentative of piastra metal plate, piaster. See plaster Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for plastron
  • Pull the plastron away from the carapace as you cut skeletal muscle attachments.
  • In older individuals the plastron may be worn smooth and growth rings not as apparent.
  • The plastron is pale yellow with the scutes usually worn.
  • The plastron of males is concave, while females have a flat or slightly convex plastron.
  • The plastron, or lower shell, is yellow with dark blotches symmetrically arranged.
  • Its plastron looks similar to that of the wood turtle.
  • The bottom shell or plastron is yellow, marked with dark brown blotches along its margins.
  • For example, the practice of stepping on the plastron to revive the turtle may actually do more harm than good.
  • The plastron is white to yellow and the head is light brown with yellow markings.
British Dictionary definitions for plastron


the bony plate forming the ventral part of the shell of a tortoise or turtle
Derived Forms
plastral, adjective
Word Origin
C16: via French from Italian piastrone, from piastra breastplate, from Latin emplastrumplaster
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
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Word Origin and History for plastron

c.1500, from Middle French plastron "breastplate," from Italian piastrone, augmentative of piastra "breastplate, thin metal plate" (see piaster). As an animal part, from 1813; as an article of dress, 1876.

Online Etymology Dictionary, © 2010 Douglas Harper
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