a purple-flowered plant (Tragopogon porrifolius) of the composite family, with long, white, edible, fleshy roots having an oysterlike flavor; oyster plant
See salsify in American Heritage Dictionary 4
(sălˈsə-fē, -fīˌ)
nounpl.sal·si·fies In both senses also called oyster plant, vegetable oyster.
A European plant (Tragopogon porrifolius) having grasslike leaves, purple flower heads, and an edible taproot.