A dialectal or archaic name for certain types of climbing plants or vines, possibly the butcher's broom or other sharp-leaved plants.
From butter + bough (Old English bog, branch or limb). This appears to be a folk compound whose original meaning connection is unclear; possibly referencing thorny growth or medicinal properties.
Old plant names like butterbough are linguistic mysteries—they often survive only in regional dialects and herbals, telling us what common people cared about when naming plants, usually flavor, medicinal use, or how they felt to touch.
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