(1):

(n.) 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.

(2):

(n.) 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.