plastron

UK: /ˈplæstrən/ US: (plas′trən)

WordReference Random House Unabridged Dictionary of American English © 2025

plas•tron  (plas′trən), n. 

1. Heraldry a piece of plate armor for the upper part of the torso in front.
2. Sport [Fencing.] a quilted pad worn over part of the torso, for protection.
3. Clothing an ornamental front piece of a woman's bodice.
4. Clothing the starched front of a shirt.
5. Zoology the ventral part of the shell of a turtle.

• Italian piastrone, augmentative of piastra metal plate, piaster. See plaster
• Middle French
• 1500–10

Collins Concise English Dictionary © HarperCollins Publishers::

plastron / ˈplæstrən/ noun

1. the bony plate forming the ventral part of the shell of a tortoise or turtle

Etymology: 16th Century: via French from Italian piastrone, from piastra breastplate, from Latin emplastrum plaster

ˈplastral adjective