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(Military) (formerly) a muster of men in a particular area in Scotland to show that they were properly armed
[C16: from Northern English wapen, from Old Norse vápn weapon + schaw show]
wap•pen•shaw(ˈwɒp ənˌʃɔ, ˈwæp-)
a periodic review of troops formerly held in Scotland to satisfy military chiefs that their men were loyal and properly armed.