\Mas"ter*wort`\, n. (Bot.)
(a) A tall and coarse European umbelliferous plant
    ({Peucedanum Ostruthium}, formerly {Imperatoria}).
(b) The {Astrantia major}, a European umbelliferous plant
    with a showy colored involucre.
(c) Improperly, the cow parsnip ({Heracleum lanatum}).