Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
rectrix, īcis, f. [rector], she that leads or guides; a directress, governess, mistress (post-Aug.): animam velut aurigam rectricemque membrorum, Col. 3, 10, 9: sapientia domina rectrixque est, Sen. Ep. 85, 32: Italia rectrix parensque mundi altera, Plin. 37, 13, 77, § 201.