A plant or bush associated with the crouper (a strap under a horse's tail); the specific plant variety is unclear from historical sources.
From crouper (a strap fastening equipment to a horse's croupe) + bush (vegetation). This appears to be a regional or obsolete plant name without clear modern botanical identification.
Old plant names often combined the animal they were used with—'crouperbush' was probably named because it resembled or was used to make the strap that goes under horses' tails!
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