Hypertext Webster Gateway: "bullweed"
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Knapweed \Knap"weed`\, n. (Bot.)
The black centaury ({Centaurea nigra}); -- so called from the
knoblike heads of flowers. Called also {bullweed}.
From Webster's Revised Unabridged Dictionary (1913) (web1913)
Bullweed \Bull"weed`\, n. [Bole a stem + weed.] (Bot.)
Knapweed. --Prior.
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