An archaic or dialectal word for a horse, particularly a workhorse or inferior horse.
From Middle English capple or capul, possibly from Old French caple or from a Scandinavian source; the exact origin is uncertain but it meant a working horse or nag.
The word capple is so old that it's almost vanished from English, but it survives in Scottish dialect and historical texts, and it's related to the word 'caparison' (fancy horse gear)!
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