mullein

As a noun mullein

is any of several european and asian plants, of the genus verbascum , that have yellow flowers and downy leaves; the (velvet plant).

As an adjective undefined is

lacking a definition or value.

As nouns the difference between lungwort and mullein

is that lungwort is any of various European plants, of the genus genus: Pulmonaria, that were once used to treat respiratory disorders while mullein is any of several European and Asian plants, of the genus Verbascum, that have yellow flowers and downy leaves; the velvet plant.

As nouns the difference between mullen and mullein

is that mullen is alternative form of lang=en while mullein is any of several European and Asian plants, of the genus Verbascum, that have yellow flowers and downy leaves; the velvet plant.

As a proper noun Mullen

is {{surname|lang=en}.