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poleyn

American  
[poh-leyn] / ˈpoʊ leɪn /

noun

Armor.
  1. a piece for the knee, made of plate or leather.


poleyn British  
/ ˈpəʊleɪn /

noun

  1. Also called: kneecap.  a piece of armour for protecting the knee

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of poleyn

1350–1400; Middle English poleyn, polayne < Old French po ( u ) lain < ?