What does "plastron" mean?

Plastron: (Anc. Armor) An iron breastplate, worn under the hauberk.

Additional senses

  1. 2.(Anat.) The ventral shield or shell of tortoises and turtles. See Testudinata.
  2. 3.A trimming for the front of a woman's dress, made of a different material, and narrowing from the shoulders to the waist.

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