Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† măgŭdăris and măgydăris (-dĕris), is, f., = μαγύδαρις, the stalk, acc. to others, the root or the juice of the plant laserpitium, Plaut Rud. 3, 2, 16; Plin. 19, 3, 15, § 45; cf. Prisc. p. 757 P.