Definition of plastron
1 a : a metal breastplate formerly worn under the hauberk b : a quilted pad worn in fencing to protect the chest, waist, and the side on which the weapon is held
2 : the ventral part of the shell of a tortoise or turtle consisting typically of nine symmetrically placed bones overlaid by horny plates
3 a : a trimming like a bib for a woman's dress b : dickey 1a
4 : a thin film of air held by water-repellent hairs of some aquatic insects
Origin of plastron
Middle French, from Old Italian piastrone, augmentative of piastra thin metal plate — more at piastre
First Known Use: circa 1507
Learn More about plastron
Britannica.com: Encyclopedia article about "plastron"
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