Lewis & Short

in-sincērus, a, um, adj., not genuine, not pure, adulterated, spoiled; not honest or candid, insincere (poet. and in post-Aug. prose).

  1. I. Lit.: cruor, Verg. G. 4, 285: acies, imperfect, Prud. Ham. 4.
  2. II. Trop.: philosophus, Gell. 5, 3, 7: oblatio, Ambros. de Cain et Abel, 2, 6, § 18; id. in Psa. 118, Serm. 11, § 20.