adder's tongue

Short definition from Wiktionary

Noun

1. 1
   Any of several ferns in the genus Ophioglossum, whose spores are produced on a spike resembling a serpent's tongue.
2. 2
   A lily in the genus Erythronium, other common names of which include fawn lily, trout lily and dog's tooth violet.
3. 3
   Hart's tongue (fern) (Asplenium scolopendrium, syn. Phyllitis scolopendrium).
4. 4
   early-purple orchid, early spring orchis Orchis mascula
5. 5
   Alternative form of adder's tongue.