Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† taura, ae, f., = ταῦρα, a barren, hybrid cow, a free-martin, Varr. R. R. 2, 5, 6; Col. 6, 22, 1; cf. Fest. pp. 352 and 353.