• Webster's Revised Unabridged Dictionary
    • Backpiece A piece of plate armor protecting the back; -- it is worn as part of a cuirass.
    • Backpiece A piece, or plate which forms the back of anything, or which covers the back.
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Century Dictionary and Cyclopedia
    • n backpiece A piece at the back of something; specifically, a piece of armor which covered the back and was connected with the breastplate by straps and buckles, hooks, and the like. See back and breast, under back, n.
    • ***


Webster's Revised Unabridged Dictionary
Back, n. or a. + piece, plate,.


In literature:

I will place my hand on the tree there, and do you unfasten the shoulder and waist straps of my breast and backpieces.
"The Young Carthaginian" by G.A. Henty
A breastplate and backpiece from a light suit of armor (probably a pikeman's suit) were found in a refuse pit.
"New Discoveries at Jamestown" by John L. Cotter