Variant or alternative spelling of claymore; a large Scottish broadsword with a distinctive cross-shaped hilt, used in medieval and early modern times.
From Scottish Gaelic claidheamh mòr 'great sword' (claidheamh 'sword' + mòr 'great'). The spelling 'glaymore' represents dialectal pronunciation variations of this Gaelic loanword.
The claymore/glaymore shows how Gaelic words got mangled by English speakers—'claidheamh mòr' sounded like 'claymore' to English ears, and nobody bothered to fix the spelling for centuries.
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