noun

• (now rare) A plant of the genus Pimpinella, especially burnet saxifrage (Pimpinella saxifraga).
• Any of various plants of the genus Anagallis, having small red, white or purple flowers, especially the scarlet pimpernel (Anagallis arvensis).
• Sanguisorba spp.
• Great burnet (Sanguisorba officinalis)
• Salad burnet (Sanguisorba minor).
• (Canada, US) A yellow pimpernel (Taenidia integerrima)
• (figurative) Someone resembling the fictional Scarlet Pimpernel; a gallant dashing resourceful man given to remarkable feats of bravery and derring-do in liberating victims of tyranny and injustice.