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.
A yellow pimpernel (Taenidia integerrima)
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.