[scarlet pimpernel] n (1855) 1: a common pimpernel (Anagallis arvensis) having scarlet, white, or purplish flowers that close in cloudy weather
2. [Scarlet Pimpernel, assumed name of the hero of The Scarlet Pimpernel (1905), novel by Baroness Orczy]: a person who rescues others from mortal danger by smuggling them across a border