Lung"wort` (?), n. (Bot.) (a) An herb of the genus Pulmonaria (P. officinalis), of Europe; -- so called because the spotted appearance of the leaves resembles that of a diseased lung. (b) Any plant of the genus Mertensia (esp. M. Virginica and M. Sibirica) plants nearly related to Pulmonaria. The American lungwort is Mertensia Virginica, Virginia cowslip. Gray.

Cow's lungwortmullein. -- Sea lungwort, Mertensia maritima, found on the seacoast of Northern Europe and America. -- Tree lungwort, a lichen (Sticta pulmonacea) growing on trees and rocks. The thallus is lacunose, and in appearance somewhat resembles the lungs, for diseases of which it was once thought a remedy.