The Collaborative International Dictionary of English v.0.48:

Nipplewort \Nip"ple*wort`\ (n[i^]p"p'l*w[^u]rt`), n. (Bot.)
   A yellow-flowered composite herb (Lampsana communis),
   formerly used as an external application to the nipples of
   women; -- called also dock-cress.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Wartwort \Wart"wort`\, n. (Bot.)
   A name given to several plants because they were thought to
   be a cure for warts, as a kind of spurge (Euphorbia
   Helioscopia), and the nipplewort (Lampsana communis).
   [1913 Webster]