Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
† delta, ae, f. or indecl. n., = δέλτα, the fourth letter of the Greek alphabet, delta, Δ: non formam at vocem deltae gero Romuleum D, Aus. Idyll. de lit. monos. 14; so (but with gender undetermined) Mel. 2, 7, 14.