Definition of "plastron" [plas•tron]

• A metal breastplate worn under a coat of mail. (noun)
• A quilted pad worn by fencers to protect the torso and side. (noun)
• A trimming on the front of a bodice. (noun)
• The front of a man's dress shirt. (noun)
• The front panel of the tunic of a uniform, usually of a different color than the rest. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "The belly was covered by a shell, the so-called plastron, in pretty much the same way as that of a modern sea turtle."
• "Just wondering if the plastron is the modern reincarnation of the colonial stomacher?"
• "The underneath of any tortoise's carapace is called the plastron and it's unique, like a fingerprint."