Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
1. ancus appellatur, qui aduncum bracchium habet et exporrigi non potest, Paul. ex Fest. p. 19 Müll. [v. ango].
2. Ancus (Marcius), i, m. [v. ango] (prop. a servant, as bending, crouching; hence = ancus Martius = θεράπων Ἄρεως, servant of Mars), the fourth king of Rome, A.U.C. 116-140, said to have been the grandson of Numa by Pompilia, Cic. Rep. 2, 18, 33; 2, 3, 5; Varr. Fragm. p. 241 Bip.; Liv. 1, 32 sqq.; Verg. A. 6, 815; Hor. C. 4, 7, 15; Ov. F. 6, 803 al.