What does "breastplate" mean?

Breastplate: A piece against which the workman presses his breast in operating a breast drill, or other similar tool.

Additional senses

  1. 2.A strap that runs across a horse's breast. Ash.
  2. 3.(Jewish Antiq.) A part of the vestment of the high priest, worn upon the front of the ephod. It was a double piece of richly embroidered stuff, a span square, set with twelve precious stones, on which were engraved the names of the twelve tribes of Israel. See Ephod.

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