• WordNet 3.6
    • n plastron (zoology) the part of a turtle's shell forming its underside
    • n plastron a large pad worn by a fencer to protect the chest
    • n plastron a metal breastplate that was worn under a coat of mail
    • n plastron the front of man's dress shirt
    • n plastron the ornamental front of a woman's bodice or shirt
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Webster's Revised Unabridged Dictionary
    • Plastron A piece of leather stuffed or padded, worn by fencers to protect the breast.
    • Plastron A trimming for the front of a woman's dress, made of a different material, and narrowing from the shoulders to the waist.
    • Plastron (Anc. Armor) An iron breastplate, worn under the hauberk.
    • Plastron (Anat) The ventral shield or shell of tortoises and turtles. See Testudinata.
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Century Dictionary and Cyclopedia
    • n plastron A breastplate; a garment or part of a garment covering the breast. Specifically— The early breastplate worn under the hauberk or broigne: one of the earliest pieces of plate-armor introduced in the European middle ages. C. Boutell, Arms and Armour in England
    • n plastron In herpetology: The ventral part of the shell of a chelonian or testudinate; the lower shell, or under side of the shell, of a turtle or tortoise: more or less opposed to carapace. The plastron is wholly an exoskeletal or integumentary structure, in which no bones belonging to the endoskeleton or skeleton proper are found. It consists of a number, typically nine, of separate dermal bones, developed in membrane, and covered with horny epidermis, or tortoise-shell. The nine typical pieces are one median and four pairs lateral, called entoplastron, epiplastron, hyoplastron, hypoplastroan, and xiphiptastron. Formerly, when these were supposed to contain or represent sternal elements, they were respectively named entosternum epistemum, hyosternum, hypoternum, and xiphisternum. The plastron is usually immovable, like the carapace, but may be variously hinged, in some cases so as to shut the animal in completely. See also cuts under carapace, Pleurospondylia, and Chelonia.
    • n plastron One of the similar exoskeletal plates developed upon the under side of the body of certain Amphibia, as the Labyrinthodonta.
    • n plastron In mammalogy, the ventral shield or cuirass of the glyptodons or fossil armadillos.
    • n plastron In anatomy, the sternum with the costal cartilages attached, as removed in autopsies.
    • n plastron In ornithology, a colored area on the breast or belly of a bird, like or likened to a shield.
    • n plastron In the Echinodermata, a space surrounded by the subanal fasciole lying beneath the anus, in spatangoid echinoids.
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Chambers's Twentieth Century Dictionary
    • n Plastron plas′tron a breast-plate: a detachable part of a woman's dress hanging from the throat to the waist: a man's shirt-bosom: a fencer's wadded shield of leather worn on the breast: the ventral part of the shell of a chelonian or testudinate, the lower shell of a turtle or tortoise: the sternum with costal cartilages attached
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Webster's Revised Unabridged Dictionary
F. plastron, breastplate, plastron, LL. plastra, a thin plate of metal. See Plaster


In literature:

Elle, blanchisseuse de fin, a developpe un secret dans la facon d'empeser les plastrons de chemises.
"Punch, Or The London Charivari, VOL. 100. Feb. 28, 1891" by Various
The bodice was of the plain, and it had a plastron, or waistcoat front, of the plaid.
"The Girl's Own Paper, Vol. VIII: No. 356, October 23, 1886." by Various
The most highly developed sternum (according to this definition) is the plastron of the tortoise, whose structure it dominates (p. 103).
"Form and Function" by E. S. (Edward Stuart) Russell
That came from the curb-bit and bridle hanging on the wall, or perhaps from the plastron, foils, and gauntlets over the mantle.
"Lorraine" by Robert W. Chambers
The land tortoises have the strongest plastrons.
"The Western World" by W.H.G. Kingston
Please try to understand, too, that this is no battle with masks and plastrons and nicely padded buttons.
"The Dark Star" by Robert W. Chambers
The use of a species of corslet, (plastron,) to prevent future pressure on the abdomen.
"North American Medical and Surgical Journal, Vol. 2, No. 3, July, 1826" by Various
That plastron she now wore.
"Eden" by Edgar Saltus
Composed of fifteen thicknesses of Italian taffeta, this plastron consisted of a vest and a large belt.
"Marie Antoinette and the Downfall of Royalty" by Imbert de Saint-Amand
In some, the plastron or lower surface of the shell of the male is slightly concave in relation to the back of the female.
"The Descent of Man and Selection in Relation to Sex" by Charles Darwin
Brumwell suggested that pressure on the plastron of the male had forced the water out his nostrils.
"Natural History of the Ornate Box Turtle, Terrapene ornata ornata Agassiz" by John M. Legler
It is a thin plastron, flattened, and much widened.
"Trees. A Woodland Notebook" by Herbert Maxwell
It is a thin plastron, flattened, and much widened.
"Extinct Birds" by Walter Rothschild
Most comments pertain to a description of the bony carapace and plastron, which Geoffroy depicts in Plate 4.
"North American Recent Soft-shelled Turtles (Family Trionychidae)" by Robert G. Webb
The plastron is hinged at one side, furnished with a latch, and opens like a door.
"Taxidermy and Zoological Collecting" by William T. Hornaday
Note the ligaments which attach the plastron to the shoulder and pelvic girdles.
"Elementary Zoology, Second Edition" by Vernon L. Kellogg
The double plastron dropped, the carapace fell down: Haidia stood revealed.
"Astounding Stories of Super-Science January 1930" by Victor Rousseau