Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
in-fācundus, a, um, adj., ineloquent (not in Cic. or Cæs.): vir acer, nec infacundus, Liv. 4, 49, 12; Suet. Claud. 40; Gell. 18, 3, 6.
Comp.: infacundior, Liv. 7, 4, 4.