Pauldron

A pauldron (sometimes spelled pouldron or powldron) is a component of plate armour, which evolved from spaulders in the 15th century. As with spaulders, pauldrons cover the shoulder area. Pauldrons tend to be larger than spaulders, covering the armpit, and sometimes parts of the back and chest. Pauldrons typically consists of a single large dome-shaped piece to cover the shoulder (the "cop") with multiple lamés attached to it to defend the arm and upper shoulder. On armours designed for mounted combat, whether in the tournament or the field, the pauldrons would be usually be assymetrical, with one pauldron sporting a cut-away to make room for a lance-rest.
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(n.)
A piece of armor covering the shoulder at the junction of the body piece and arm piece.
  

The larger defense of the shoulder where one or more large plates extended the defense of the shoulder to include the underarm and part of the chest and back. First used in an inventory C. 1397, there are no other references prior to 1450, though modern students apply the term to any shoulder defense where the coverage extends beyond the arm-hole of the cuirass . Almost always made in iron , and very rarely adorned except for the fluting in some later German examples. Developed at the very end of the 14th century, the style became fully "international" during the 15th century, following Italian or Milanese and Gothic styles and methods of construction. During the period, it seems that spaulder , pauldron and rerebrace