thistle butterfly

thistle butterfly (plural thistle butterflies)

1. A butterfly of the genus Vanessa, especially the painted lady Vanessa cardui.
   • 1828 July, “Emigration of Butterflies”, in Benjamin Silliman, editor, The American Journal of Science and Arts, volume 14, page 388:

     The butterflies were all of one description and among the most beautiful of our country. They were caught very easily in a net, and were recognized as the thistle butterfly, called in French, the belle-dame.

• thistle butterfly in Merriam-Webster[1]