armpiece noun2 •A piece of armour that protects the arm.“Go, my good St. John,—in an arm-piece of the Milanese armor that hangs on the wall, thou’lt find the Seal!” — 1881 •(informal) A decorative companion.He'd decided to take her because she was the best looking armpiece of all, and as long as she kept her mouth shut, he'd be the envy of every man there. — 2000 formsarmpieces
